Innocent capacitor blamed for ASUS RTX 5090 Astral catching fire

00:20:41
https://www.youtube.com/watch?v=aHRlYQas4xw

Summary

TLDRBuildzoid examines a reported failure in an RTX 590 graphics card that involved a blown power stage. He reflects on the frequent failures of high-end Nvidia GPUs and presents a critical view of blaming capacitors for such issues. Instead, he advocates for understanding the actual causes of power stage failures, which may include manufacturing defects or poor soldering quality. Throughout the video, he clarifies that solid polymer capacitors are highly reliable, emphasizing the misunderstanding surrounding their reliability. Buildzoid shares personal experiences related to repairing GPUs and comments on the need for better designs to avoid catastrophic failures, ultimately recommending that affected card owners seek replacements from manufacturers.

Takeaways

  • ⚡️ Power stage failures are common in high-end GPUs.
  • 🔧 Capacitors are largely reliable if used correctly.
  • ❗️ Misunderstanding leads to blaming capacitors for failures.
  • 🔍 Power stages can fail due to manufacturing defects.
  • ⚠️ Design flaws in GPUs can lead to catastrophic failures.
  • 💡 Capacitors generally do not fail unless installed backwards.
  • 🛠 Repairing GPUs often reveals common failure points.
  • 🔋 Better design practices could prevent power stage issues.
  • 🔥 High side MOSFET shorts are critical failure points.
  • 💪 Solid polymer capacitors are considered indestructible.

Timeline

  • 00:00:00 - 00:05:00

    The video begins with Buildzoid discussing a photo of a damaged RTX 590 graphics card, specifically noting a blown power stage, a common issue seen in high-end Nvidia GPUs like the RTX 3090. He shares his disbelief over the premature failure of this card and emphasizes that without more evidence, it remains unclear if the failure was due to a manufacturing defect or not.

  • 00:05:00 - 00:10:00

    Buildzoid expresses frustration over an article that inaccurately blames a capacitor for the power stage explosion, explaining that capacitors, especially solid polymer types, are quite durable and rarely fail. He describes different scenarios that might cause capacitor failures, such as incorrect installation or overheating, but asserts that these were not the cases here.

  • 00:10:00 - 00:15:00

    The discussion shifts to detailing the potential reasons for the actual power stage failure in the GPU. Buildzoid considers things like poor soldering quality or control circuit issues but leans towards bad soldering as the most probable cause. He asserts that ASUS should replace the card, as the issue does not lie with the user.

  • 00:15:00 - 00:20:41

    Finally, Buildzoid sums up his points, stressing the misconception that capacitors frequently fail in these situations. He calls for better designs in high-end GPUs to prevent power stage failures and firmly concludes that this incident is almost certainly not a capacitor failure, encouraging viewers to support his channel.

Show more

Mind Map

Video Q&A

  • What is the main topic of the video?

    The main topic is the analysis of a blown power stage in an RTX 590 graphics card.

  • What components are discussed in relation to failures?

    The focus is on solid polymer capacitors and power stages in graphics cards.

  • Can capacitors fail?

    While capacitors can fail, solid polymer capacitors are generally reliable unless misused.

  • What can cause a power stage failure?

    Power stage failures may result from manufacturing defects, soldering quality, or control circuitry issues.

  • What does Buildzoid suggest about replacing the card?

    He suggests that the card owner should have the card replaced by Asus due to the failure.

  • Are power stages common points of failure?

    Yes, power stages are known to fail more frequently than capacitors.

  • What design flaw is mentioned regarding power delivery?

    The design does not include safety features like fuses, leading to catastrophic failures.

  • What is Buildzoid's stance on blaming capacitors?

    He strongly opposes blaming capacitors for power stage failures.

View more video summaries

Get instant access to free YouTube video summaries powered by AI!
Subtitles
en
Auto Scroll:
  • 00:00:00
    hey guys buildzoid here and today we're
  • 00:00:02
    going to be doing more low effort
  • 00:00:03
    content um now I didn't think I'd be
  • 00:00:05
    making a video about this when I first
  • 00:00:07
    saw it on Reddit because I took a look
  • 00:00:08
    at this photo and I was like hm that
  • 00:00:10
    looks like a dead power stage and the
  • 00:00:12
    thing is this is an RTX 590 and RTX 59s
  • 00:00:15
    are high-end Nvidia gpus and the thing
  • 00:00:18
    about high-end Nvidia gpus is that they
  • 00:00:20
    tend to have the power stages fail like
  • 00:00:23
    a lot remember all those RTX 309s that
  • 00:00:25
    were dying trying to play new world yeah
  • 00:00:28
    they were just blowing the power stage
  • 00:00:31
    um so I am not surprised to see a photo
  • 00:00:34
    of a RTX 590 with a blown power stage
  • 00:00:38
    cuz that just seems like something a
  • 00:00:40
    5090 would eventually do at some point
  • 00:00:43
    though I will say I am surprised to see
  • 00:00:44
    it on a stxs or I mean an astral and I
  • 00:00:48
    am surprised that it happened so soon um
  • 00:00:51
    but ultimately without the card in hand
  • 00:00:53
    or more such failures it's impossible to
  • 00:00:57
    say if this was anything more than like
  • 00:00:59
    a freak man ufacturing defect
  • 00:01:02
    so yeah I didn't think I'd be making a
  • 00:01:05
    video about this so then why am I making
  • 00:01:06
    a video about it well I saw this article
  • 00:01:09
    on video cards accusing an innocent
  • 00:01:12
    capacitor of what I am 99% certain is a
  • 00:01:15
    power stage
  • 00:01:16
    explosion and I'm guessing video cards
  • 00:01:19
    got this uh capacitor accusation from
  • 00:01:22
    this comment over here this looks to be
  • 00:01:24
    a blown capacitor and this is just a
  • 00:01:26
    thing that annoys me to no end um for
  • 00:01:29
    some reason people who don't repair gpus
  • 00:01:32
    or motherboards blame capacitors for
  • 00:01:36
    like things that capacitors just don't
  • 00:01:39
    do okay like I'm assuming the reason why
  • 00:01:43
    the capacitor is being accused of what
  • 00:01:44
    is evidently a power stage explosion is
  • 00:01:46
    because of this discoloration over here
  • 00:01:49
    but I am relatively certain that that
  • 00:01:51
    discoloration is actually the internals
  • 00:01:53
    vaporized internals of a power stage I
  • 00:01:55
    guess vaporized and recondensed
  • 00:01:57
    internals of a power stage um so um yeah
  • 00:02:02
    that that capacitor is not at fault here
  • 00:02:05
    the thing is uh in my exper like I've
  • 00:02:07
    repaired a few gpus I've repaired so
  • 00:02:10
    many gpus I can't actually tell you how
  • 00:02:12
    many I've repaired because I've lost
  • 00:02:13
    track of them I've repaired a couple
  • 00:02:15
    motherboards I have never repaired a GPU
  • 00:02:19
    or a motherboard by replacing a solid
  • 00:02:23
    polymer capacitor because these are
  • 00:02:25
    basically indestructible at least if you
  • 00:02:27
    use them
  • 00:02:28
    properly there's like three ways you can
  • 00:02:31
    get these to die um and they're
  • 00:02:34
    basically like so one you could install
  • 00:02:37
    them backwards and that is a thing that
  • 00:02:38
    Asus did on a couple motherboards they
  • 00:02:40
    had a a batch of motherboards where this
  • 00:02:43
    style of polymer capacitor got installed
  • 00:02:45
    backwards and when you do that what
  • 00:02:47
    happens is these capacitors instead of
  • 00:02:49
    blocking DC current they just conduct DC
  • 00:02:52
    current so they pull a like you
  • 00:02:54
    basically end up with a lot of current
  • 00:02:55
    flowing through the capacitor the
  • 00:02:57
    capacitor gets extremely hot and in the
  • 00:03:00
    case of those Asus motherboards there
  • 00:03:01
    was like a mosfet in series with the
  • 00:03:03
    capacitor and that mosfet couldn't take
  • 00:03:05
    the current so that would usually burn
  • 00:03:06
    up um but ultimately that was caused by
  • 00:03:09
    the backwards capacitor just pulling
  • 00:03:11
    excessive amounts of current through a
  • 00:03:13
    mosfet that wasn't designed for it
  • 00:03:15
    finally enough the capacitor itself
  • 00:03:17
    didn't usually fail as far as I know and
  • 00:03:20
    I've actually kind of done the same
  • 00:03:21
    thing by accident myself I once
  • 00:03:23
    installed one of these like this style
  • 00:03:25
    of capacitor backwards on the Vore rail
  • 00:03:28
    of a Vega
  • 00:03:29
    um I did not know that that capacitor
  • 00:03:31
    was backwards until I pulled tried to
  • 00:03:34
    pull the card out of the system and
  • 00:03:36
    burnt my hand on the backwards capacitor
  • 00:03:38
    cuz it got just stupid hot um so um yeah
  • 00:03:43
    but the card was fine like it did not
  • 00:03:45
    care about the backwards capacitor at
  • 00:03:47
    all um but anyway um yeah so if you
  • 00:03:52
    install them backwards uh that that'll
  • 00:03:55
    you know cause them to pull excessive
  • 00:03:56
    current and that could eventually cause
  • 00:03:58
    them to blow up maybe but this one's not
  • 00:04:00
    backwards because we can just about make
  • 00:04:02
    out the polarity stripe so unless the
  • 00:04:05
    factory making these capacitors screwed
  • 00:04:07
    up the polarity stripe which if they did
  • 00:04:10
    like the card would not work you
  • 00:04:12
    wouldn't have one capacitor that's
  • 00:04:13
    backwards they'd be all backwards um and
  • 00:04:17
    other than that we also have the uh smt
  • 00:04:19
    adapter plate over here right to make
  • 00:04:22
    these capacitors uh surface mount and
  • 00:04:26
    that has the corners cut off to indicate
  • 00:04:28
    the polarity on one side and and yeah we
  • 00:04:30
    can see that corner is also cut off so
  • 00:04:32
    this thing is definitely not backwards
  • 00:04:34
    now alternatively you can also massively
  • 00:04:36
    over Vault these I once did that by
  • 00:04:38
    installing a 2 and2 volt capacitor on a
  • 00:04:40
    12vt rail I didn't read the label I
  • 00:04:43
    assumed it was 16 volts it wasn't um and
  • 00:04:46
    that produced a popping noise and that
  • 00:04:48
    was that it really didn't actually
  • 00:04:50
    produce a lot of drama um but uh yeah
  • 00:04:53
    also that 2 and2 volt capacitor was
  • 00:04:55
    backwards so I like nailed it it was
  • 00:04:57
    backwards and like 2 and 1 12 volts on
  • 00:04:59
    on 12 so um capacitor never stood a
  • 00:05:04
    chance um but uh this is a 16vt
  • 00:05:08
    capacitor I mean I don't know for sure
  • 00:05:11
    that it's 16 volts I can't actually see
  • 00:05:13
    the label but I'm 99% certain that it's
  • 00:05:16
    a 16vt capacitor because this card
  • 00:05:18
    literally doesn't have any other flavor
  • 00:05:20
    of 16vt capacitor also if it was like a
  • 00:05:23
    6.3 volts right like these are all 16
  • 00:05:26
    volts um so I don't like I don't see how
  • 00:05:29
    a like lower voltage capacitor would end
  • 00:05:32
    up on here um and if it was 6.3 volts or
  • 00:05:37
    2 and half volts the card wouldn't turn
  • 00:05:39
    on right this person was able to use the
  • 00:05:42
    card cuz the their PC randomly shut down
  • 00:05:45
    while browsing websites so evidently
  • 00:05:48
    those capacit like that capacitor can't
  • 00:05:50
    be massively underrated because if it
  • 00:05:52
    was they would have never been able to
  • 00:05:54
    turn the system on um so alternatively
  • 00:05:57
    you'd have to apply like 30 volts to it
  • 00:05:59
    which uh I don't know where you're going
  • 00:06:00
    to get that so nah and finally uh you
  • 00:06:04
    can overheat these though my experience
  • 00:06:06
    with doing that is usually using a heat
  • 00:06:08
    gun cuz you know I buy a lot of dead
  • 00:06:10
    gpus and on those dead gpus when you try
  • 00:06:12
    to heat gun off the dead power stage
  • 00:06:14
    well those dead power stages are often
  • 00:06:16
    very close to some polymer capacitors
  • 00:06:18
    and if you're not careful you can
  • 00:06:20
    accidentally cook the capacitor with the
  • 00:06:22
    hot air while trying to desolder the
  • 00:06:24
    dead power
  • 00:06:26
    stage so that's my experience with
  • 00:06:29
    overheating these and when you do that
  • 00:06:31
    what ends up what happens is if you
  • 00:06:33
    overheat them a little the casing swells
  • 00:06:35
    up cuz the thing is these are solid
  • 00:06:36
    polymers so they don't have any liquid
  • 00:06:38
    in them they're not designed to vent uh
  • 00:06:41
    gases or anything um and so if you
  • 00:06:44
    really overheat these they first puff up
  • 00:06:46
    cuz the casing doesn't have any way to
  • 00:06:48
    vent the internals if you start cooking
  • 00:06:50
    them um and if you keep cooking them
  • 00:06:54
    eventually the bottom of the capacitor
  • 00:06:56
    blows out um and I've had and like
  • 00:07:00
    sometimes that'll just lift the
  • 00:07:01
    capacitor up off the board a bit um but
  • 00:07:04
    I've also seen them literally shoot off
  • 00:07:06
    the board um so um yeah uh which is why
  • 00:07:10
    I now wear like safety glasses when
  • 00:07:13
    working with hot air near capacitors
  • 00:07:15
    because I really don't feel like getting
  • 00:07:17
    200 degree actually might be more than
  • 00:07:19
    200 degre by the time it blows off but
  • 00:07:21
    anyway I don't feel like having you know
  • 00:07:23
    hot capacitor shoot into my eye um that
  • 00:07:27
    doesn't sound very fun um
  • 00:07:30
    but anyway so you can cook these but you
  • 00:07:32
    like you really need to cook them basic
  • 00:07:34
    almost on purpose um also this doesn't
  • 00:07:37
    look swelled up and it doesn't look like
  • 00:07:39
    it lifted off the board at all so I'd
  • 00:07:43
    Hazard as a guess that this capacitor is
  • 00:07:45
    completely fine and so are all of the
  • 00:07:47
    other capacitors on this card now I have
  • 00:07:49
    repaired some motherboard actually I
  • 00:07:51
    don't think I ever repaired a
  • 00:07:52
    motherboard with a multi layer ceramic
  • 00:07:54
    but I have repaired some gpus with uh
  • 00:07:57
    cracked multi-layer ceramic capacitors
  • 00:08:00
    um so the problem with these is that
  • 00:08:02
    these are very rigid and pcbs are kind
  • 00:08:05
    of Bendy by comparison and so what
  • 00:08:08
    happens if you have like a multi-layer
  • 00:08:09
    ceramic near say a screw hole is that
  • 00:08:12
    the PCB will bend as the screw gets
  • 00:08:15
    insert like you know tighten down and
  • 00:08:18
    the capacitor won't so instead it'll
  • 00:08:21
    crack and when it cracks it internally
  • 00:08:23
    short circuits and then the next time
  • 00:08:25
    you apply power to the capacitor it
  • 00:08:27
    lights up like a little light bulb on
  • 00:08:29
    till and then well okay it depends on
  • 00:08:32
    what power supply is hooked up to it but
  • 00:08:35
    my experience is usually they end up
  • 00:08:37
    looking like a little orange LED um if
  • 00:08:40
    you have them hooked up to something
  • 00:08:41
    more substantial they might like fizzle
  • 00:08:44
    out pretty quickly um but they don't
  • 00:08:47
    tend to cause like the catastrophic kind
  • 00:08:50
    of damage that you get from Power stages
  • 00:08:52
    dying
  • 00:08:54
    um now the thing is
  • 00:08:56
    though um these are really small
  • 00:09:00
    relatively speaking like this is like
  • 00:09:02
    usually the kind of capacitor that is
  • 00:09:04
    susceptible to cracking due to PCB B
  • 00:09:06
    like the PCB getting bent is the larger
  • 00:09:09
    types like what we have over here
  • 00:09:12
    um these are really small alth so
  • 00:09:15
    there's no screw holes anywhere near
  • 00:09:17
    this now technically we do have a
  • 00:09:19
    thermal pad pushing down on the board so
  • 00:09:22
    that you know if that thermal pad is too
  • 00:09:24
    thick or too hard or both it could bend
  • 00:09:28
    the PCB
  • 00:09:29
    and then like maybe crack this cap like
  • 00:09:31
    these two over here or like these two
  • 00:09:33
    but like I doubt it that seems
  • 00:09:36
    incredibly unlikely like there are very
  • 00:09:39
    like there are cards out there with
  • 00:09:40
    extremely bent pcbs and and you don't
  • 00:09:43
    like you don't like I have like I I
  • 00:09:46
    think I repaired like two or three gpus
  • 00:09:49
    with cracked multiair ceramic capacitors
  • 00:09:52
    like this is very rare in my experience
  • 00:09:56
    so yeah also none of them had like
  • 00:09:59
    spectacular amounts of damage on there
  • 00:10:02
    um
  • 00:10:03
    so yeah I am I there's like to me this
  • 00:10:07
    is like 99% dead power stage
  • 00:10:12
    um
  • 00:10:14
    so that's my judgment and that's why I'm
  • 00:10:16
    making this video cuz it's just like it
  • 00:10:18
    just annoys me that capacitors which
  • 00:10:21
    generally don't fail and are borderline
  • 00:10:24
    indestructible unless misused get blamed
  • 00:10:28
    for power power stage failures which are
  • 00:10:31
    like pretty typical like that's the
  • 00:10:33
    thing that bugs me about this most is
  • 00:10:35
    like based on how like people just
  • 00:10:37
    always go like oh it's probably a
  • 00:10:39
    capacitor problem you'd think that like
  • 00:10:41
    capacitor failures are like common or
  • 00:10:43
    something but they're not like maybe on
  • 00:10:45
    cheap electronics that use Liquid
  • 00:10:47
    electrolyte capacitors capacitor
  • 00:10:49
    failures are a common issue but on gpus
  • 00:10:53
    and motherboards all of the capacitors
  • 00:10:55
    are some kind of solid polymer they're
  • 00:10:57
    basically indestructible
  • 00:10:59
    they don't
  • 00:11:01
    die other than the multi-layer Ceramics
  • 00:11:03
    but the multi-layer Ceramics are also
  • 00:11:05
    solid and also don't die unless you like
  • 00:11:08
    bend the board so I don't get how this
  • 00:11:12
    like how people just like always jump to
  • 00:11:14
    blaming the capacitors and it annoys me
  • 00:11:16
    because it's like it's not the freaking
  • 00:11:18
    capacitors it's like never the
  • 00:11:21
    capacitors so anyway
  • 00:11:24
    um yeah um that's the main reason I'm
  • 00:11:27
    making this video now on to why this
  • 00:11:29
    might have failed now um I don't think
  • 00:11:32
    this is a case of like Asus cheaping out
  • 00:11:34
    on the components cuz they're just using
  • 00:11:36
    Monolithic Power Systems mp8 6670 uh
  • 00:11:39
    Power stages I mean unless they're
  • 00:11:42
    multis sourcing the power stages for
  • 00:11:43
    this card which is possible Right like
  • 00:11:46
    we have like recently I did a video
  • 00:11:48
    about like hey you can actually get 3080
  • 00:11:49
    TI with like both uh FD MF 317s and also
  • 00:11:54
    power stages from Monolithic Power
  • 00:11:55
    Systems but I would assume like I like I
  • 00:12:00
    kind of doubt that Asus would have been
  • 00:12:01
    multis sourcing power stages for like
  • 00:12:03
    what I'm assuming is the first batch of
  • 00:12:06
    509s um so it's probably on these MP 86
  • 00:12:12
    uh uh 670 power stages um and these have
  • 00:12:17
    been used like Asus has used these on
  • 00:12:19
    like a bunch of motherboards off the top
  • 00:12:20
    of my head and I think this is the first
  • 00:12:23
    time I've ever heard of one of these
  • 00:12:24
    dying uh so I don't think this is like
  • 00:12:27
    like unless Monolithic Power systems had
  • 00:12:29
    like a defective batch I wouldn't blame
  • 00:12:32
    the power stage for this
  • 00:12:34
    um right like yeah like maybe maybe
  • 00:12:37
    there was like one one that was wonky or
  • 00:12:40
    something but I don't like this is not
  • 00:12:42
    some like bargain bucket you know power
  • 00:12:45
    stage so I don't see a reason that that
  • 00:12:47
    should fail in this application for no
  • 00:12:49
    apparent reason especially when just
  • 00:12:51
    browsing websites um now uh
  • 00:12:57
    alternatively um it could have been
  • 00:12:59
    soldered badly to the board so a concern
  • 00:13:01
    with soldering power stages is that if
  • 00:13:03
    there's too many voids in the solder cuz
  • 00:13:05
    the solder contracts as it cools um
  • 00:13:08
    which basically means it you get like
  • 00:13:11
    pockets of nothingness in inside solder
  • 00:13:13
    joints under uh surface mount components
  • 00:13:16
    with big uh P like connection pads which
  • 00:13:19
    these have the these are what the pads
  • 00:13:21
    look like so yeah that is a concern with
  • 00:13:24
    soldering of these is that you could
  • 00:13:26
    have like big gaps in the connection
  • 00:13:28
    under the power stage and that will make
  • 00:13:30
    the power stage run incredibly hot um
  • 00:13:34
    but we'd basically need like without
  • 00:13:36
    having the card in hand that's
  • 00:13:37
    impossible to to diagnose
  • 00:13:41
    um so yeah alternatively there could be
  • 00:13:43
    something wrong with the control
  • 00:13:45
    circuitry of the power stage so which
  • 00:13:47
    could be like an actual design flaw of
  • 00:13:49
    the
  • 00:13:50
    card um so it could be like running
  • 00:13:53
    wrong and then like maybe there's like
  • 00:13:55
    an issue with switching from idle to
  • 00:13:58
    high power or from you know like there
  • 00:14:00
    could be some kind of power management
  • 00:14:01
    issue or something like that um but I
  • 00:14:05
    doubt it that seems like something that
  • 00:14:07
    you you would hope that they would you
  • 00:14:10
    know catch in the development process
  • 00:14:12
    then again Nvidia has
  • 00:14:15
    been uh apparently like the 50 Series
  • 00:14:18
    development process was kind of rushed
  • 00:14:20
    but I still don't think like gpus have
  • 00:14:23
    had idle power States for years I can't
  • 00:14:25
    imagine that like the 90 has some
  • 00:14:27
    Bizarro power stage man power State
  • 00:14:29
    Management that would suddenly cause
  • 00:14:32
    power stage failures that just doesn't
  • 00:14:33
    make sense to me um so yeah so my my
  • 00:14:39
    like default assumption in this case
  • 00:14:41
    would be like oh maybe like bad
  • 00:14:42
    soldering quality on one of the power
  • 00:14:44
    stages um the main thing is or well main
  • 00:14:49
    thing like the owner of this card they
  • 00:14:52
    should just get this card replaced by
  • 00:14:53
    Asus cuz this this is not their fault
  • 00:14:56
    there's this is just like Asus sent them
  • 00:14:58
    a card with the dodgy power stage either
  • 00:15:00
    because of like soldering quality or
  • 00:15:04
    maybe the power stage itself was dodgy
  • 00:15:06
    like something was evidently wrong with
  • 00:15:08
    it and it G like you know shorted out
  • 00:15:11
    and died um ASUS ASUS should replace the
  • 00:15:15
    card um but the thing is if this card
  • 00:15:19
    had fuses it wouldn't produce fire and
  • 00:15:22
    it wouldn't produce smoke right because
  • 00:15:25
    this initial like shutdown is like this
  • 00:15:27
    is when I think the power stage like the
  • 00:15:29
    high side mosfet died which caused the
  • 00:15:31
    system to shut down and then uh with the
  • 00:15:34
    still shorted high side mosfet the owner
  • 00:15:36
    you know power cycled the system and
  • 00:15:38
    that's what created all the fire and
  • 00:15:40
    smoke because they have a 1200 watt
  • 00:15:41
    power supply because of course they do
  • 00:15:44
    they have a 590 so so you know uh if we
  • 00:15:47
    scroll through the comments yeah they
  • 00:15:49
    have a Rog Thor 1200 wat PSU if I'm not
  • 00:15:52
    mistaken this is like a relabeled seic
  • 00:15:54
    thing or something um and so off the top
  • 00:15:58
    of my head this is is going to have an
  • 00:15:59
    overcurrent protection of over 100 amps
  • 00:16:02
    right so when a high side mosfet shorts
  • 00:16:05
    out it literally just connects the input
  • 00:16:07
    12 volts to the output now under normal
  • 00:16:11
    circumstances the way the power Stage
  • 00:16:13
    Works is that it'll be this is a 90
  • 00:16:16
    probably running 500 khz so the power
  • 00:16:19
    stage is basically using that high side
  • 00:16:21
    MOS fat to uh chop 12 volts into very
  • 00:16:25
    short pulses of 12 volts into the
  • 00:16:28
    inductor
  • 00:16:29
    at like 500,000 times a second right so
  • 00:16:32
    you get bursts of 12 volts getting
  • 00:16:34
    applied to this side of the inductor
  • 00:16:36
    500,000 times a second and through
  • 00:16:38
    inductor magic which is what we're going
  • 00:16:40
    to call it for now that like those short
  • 00:16:43
    bursts or short pulses of 12 volts get
  • 00:16:46
    turned into a much lower voltage on the
  • 00:16:49
    output side of the
  • 00:16:50
    inductor now the problem is when your
  • 00:16:53
    high side mosfet shorts shorts out it no
  • 00:16:58
    longer chop up the 12 Vols right instead
  • 00:17:00
    of getting short little tiny little
  • 00:17:02
    pulses of 12 Vols CU this is you know
  • 00:17:05
    like say an 8% pulse 500,000 times a
  • 00:17:09
    second so tiny little pulses uh yeah
  • 00:17:12
    instead of getting that you just get 12
  • 00:17:14
    volts rammed straight into the
  • 00:17:16
    inductor which means the output voltage
  • 00:17:19
    starts Rising
  • 00:17:21
    uncontrollably which this is the msvd
  • 00:17:23
    rail there's not going to be a ton of
  • 00:17:25
    capacitance relative to say VC Cor
  • 00:17:28
    there's a decent chance that the core on
  • 00:17:30
    this GPU is dead now I'm sure Asus is
  • 00:17:33
    going to be thrilled about having to pay
  • 00:17:35
    Nvidia for more GPU cores because they
  • 00:17:37
    couldn't be bothered to put a actually
  • 00:17:40
    to in defense of Asus you can't really
  • 00:17:42
    put any fuses on a 5090 because the
  • 00:17:45
    power distribution on this is just not
  • 00:17:47
    designed with any kind of safety
  • 00:17:49
    features in mind
  • 00:17:52
    um like it's like the power distribution
  • 00:17:54
    on a 5090 and a 4090 as well for that
  • 00:17:58
    matter is basically designed around the
  • 00:18:00
    assumption that things don't go wrong um
  • 00:18:04
    and when things do go wrong you get fire
  • 00:18:06
    and smoke spitting out of the card um
  • 00:18:09
    because yeah you get like the entire
  • 00:18:10
    output of the power supply getting
  • 00:18:12
    dumped through this power stage through
  • 00:18:14
    that inductor and through the M like the
  • 00:18:17
    through part of the GPU core
  • 00:18:20
    um so yeah because basically like your
  • 00:18:24
    power supply like the 1200 a 1200 watt
  • 00:18:27
    power supply right when when it sees
  • 00:18:29
    that shorted out power stage if that
  • 00:18:31
    shorted out power stage is not low
  • 00:18:33
    enough resistance to immediately trip
  • 00:18:35
    the short circuit protection it will
  • 00:18:37
    just dump current into it which is how
  • 00:18:40
    you get all of the fire and smoke and
  • 00:18:42
    also probably a dead GPU in this case um
  • 00:18:47
    and the thing is if there was a fuse in
  • 00:18:48
    front of that power
  • 00:18:50
    stage in you know like that first
  • 00:18:53
    failure would have hopefully taken the
  • 00:18:55
    fuse out and then when the owner goes to
  • 00:18:58
    to turn the card on again you don't get
  • 00:19:00
    any fire because you can't apply 12
  • 00:19:02
    volts to a dead power stage a second
  • 00:19:04
    time
  • 00:19:07
    um but
  • 00:19:09
    um
  • 00:19:11
    yeah um the main point of this video was
  • 00:19:14
    though please don't blame capacitors for
  • 00:19:16
    power stage
  • 00:19:18
    failures capacitors are really really
  • 00:19:21
    reliable power stages on the other hand
  • 00:19:24
    even high-end ones aren't like I have a
  • 00:19:26
    stxs 2080 TI with a Texas Instruments
  • 00:19:30
    like 80 amp power
  • 00:19:32
    stage and I had to replace it because
  • 00:19:35
    one of them blew up I don't know why it
  • 00:19:36
    blew up but it did I have like a he I
  • 00:19:39
    have a whole bunch of 980 TI that had
  • 00:19:41
    dead power stages I just like there's
  • 00:19:44
    that's the I repaired two different 309s
  • 00:19:46
    that had dead power stages admittedly
  • 00:19:48
    those were like cheap power stages not
  • 00:19:50
    high-end ones but like power stages
  • 00:19:52
    failing is a thing that happens a lot so
  • 00:19:55
    like maybe we should design the ex Uber
  • 00:19:59
    expensive gpus to resist power stage
  • 00:20:02
    failures a bit better than just hoping
  • 00:20:04
    that the power stages don't die cuz they
  • 00:20:07
    do die a
  • 00:20:09
    lot um anyway this is almost certainly
  • 00:20:13
    not a capacitor failure um and that's
  • 00:20:16
    that's it for the video so hopefully you
  • 00:20:18
    found this somewhat interesting if not
  • 00:20:19
    particularly useful and that's it so
  • 00:20:24
    thanks for watching and oh if you'd like
  • 00:20:27
    to support the channel there are links
  • 00:20:28
    in the description you could check those
  • 00:20:30
    out it would be very much
  • 00:20:31
    appreciated and uh am I forgetting
  • 00:20:35
    anything I don't think so so I guess
  • 00:20:36
    I'll just hit the stop button now thanks
  • 00:20:38
    for watching and goodbye
Tags
  • RTX 590
  • power stage
  • capacitor failure
  • Nvidia
  • GPU repair
  • Buildzoid
  • solid polymer capacitors
  • manufacturing defects
  • soldering
  • power delivery