Dell OptiPlex GX270 - multiple bad cap failures

[Toasty]

Re: Dell OptiPlex GX270 - multiple bad cap failures

Chinese cat...

robster craw.

[Uranium-235]

Re: Dell OptiPlex GX270 - multiple bad cap failures

HAHA. guess where dell shipped their mistake?

so as some of you know, I well (USED) to volunteer @ goodwill computer works. In the back, I found a palette of about at least 20-30 Dell GX 270. Every single one of them with bad caps

[ratdude747]

Re: Dell OptiPlex GX270 - multiple bad cap failures

were they cheap? might have been worth taking when they hit the sales floor for a recap

then again, the gx2__ series is known to be a bunch of easy bake ovens in disguise .

[etnietering]

Re: Dell OptiPlex GX270 - multiple bad cap failures

back in high school there was a semester where we'd have at least one computer go a week, they'd just shut off and never work again. That was 3 or 4 years ago though, I don't remember what kinds they were or anything...

[Northeastern292]

Re: Dell OptiPlex GX270 - multiple bad cap failures

My trig (we in NYS call it Math B) teacher one day found her GX270 unusable. There was another working one in the class, so she used that, but now when I look back, it probably was a bunch of blown caps.

[Jay_Slim]

Re: Dell OptiPlex GX270 - multiple bad cap failures

I had no idea there was such a huge problem with these GX270's until I went online to shop for a graphics card.
Somehow, during my search I wound up on these forums reading about the bad capacitors.

I purchased mine back in Feb 09 from Dell Direct Sales, where all their leased stuff winds up.
Anyways, I open mine up and lo and behold, I have a bulging capacitor right by the DIMM.
I actually remember there being a whole sh!tload of them on sale at the time.

I guess I should've done a little more research on them before purchasing but to late now.

How long does/can it take before my computer fails?

[deckart]

Re: Dell OptiPlex GX270 - multiple bad cap failures

We have the same problem in the UK.I'm a Field Engineer servicing Government IT equipment,which,unfortunately is all Dell.All GX270's,whether NFF or SFF,GX280's included,suffer from MB failure with monotonous regularity.Generally the whole IT infrastructure is so antique due to spending cuts,it amazes me how these people manage to even log on.The paranoia about accessing user information via USB sticks or stolen HDD means their systems are crippled by background running AV scans,which,due to none prior testing,means to just boot takes any where between 20-45 minutes!.
If you calculate the number of employees to that time,no wonder accountants start getting their calculators out and start recommending lay offs.

[Jay_Slim]

Re: Dell OptiPlex GX270 - multiple bad cap failures

Only Nichicon HM and HN series had the problems and it's only those two you have to worry about date codes on.

-

I have 7 or 8 of those boards here now so I took some voltage readings and I modded your drawing to show what I found.
[ Was going to next week anyway for my own info. ]
Voltages taken with system was sitting at BIOS screen, all RAM slots filled, but with nothing in any add-in slots so condition was unloaded.


Note: The original cap sizes vary by board version (tower vs desktop vs SFF vs USFF) as well as by make/series of cap from board to board within those versions so I'll relate what I usually see. I absolutely have NOT seen all variations so other combinations are very likely.

Letters reference to drawing.

A: These are two of your swollen caps - [2] 1500uF 6.3v - 10mm.
[Other board versions use [2] 1800uF 6.3v 8mm here.]
These are filtering +5v either to whole board or to RAM regulators.
Usually see Rubycon MCZ // Panasonic FL,FJ // Nichicon HN
Stay with 6.3v or more.
>> Your replacements look fine for these.

B: These are your other swollen caps - [3] 1500uF 6.3v - 10mm.
These are to RAM. [Measured voltage was slightly high because RAM wasn't doing anything even though both slots were filled. Normal would be around 2.5-2.6v.]
- Usually see Rubycon MCZ // Panasonic FL,FJ // Nichicon HN
>> Your replacements are fine for these but 4v caps should work too.

C: General caps to slots and IC chips on board. - [4] 820uF 6.3v - 8mm.
- Usually see Rubycon MBZ or Panasonic FJ or Nichicon HM
These are on +1.5v so 2.5v caps should be fine.
These blow sometimes but not so often as the others.

D: The "I dunno cap" that is often blown - [1] 680uF 10v - 8mm.
The original caps seem to have problems in that spot and I suspect there is more ripple there than they can handle.
- Usually see Rubycon MBZ or Panasonic FJ or Nichicon HM
I think using a 680uF - 4v[up] solid polymer here is a REAL GOOD idea.
- I would replace this cap with a poly just because it blows so often.
I think it's only 10v to get lower ESR and keep it an 8mm 680uF so presumably the 680uF value is important here.

E: VRM-output caps. - [9] 1800uF 6.3v 8mm
- Usually see Rubycon MCZ or Panasonic FL or Nichicon HN
Down to 2.5v is okay. - Nine 820uF-2.5v solid polymer should be fine.
This is a common mod and it works fine.
[ESR is more important than uF here but you do need -some- uF.]

F: VRM-input caps. - [3] 1800uF 16v - 10mm.
- Usually see Rubycon MCZ or Panasonic FL or Nichicon HN
Must be 16v. - Three 330uF to 470uF at 16v solid polymer should be fine.
Many moddin' folks use [3] 330uF here with no problems on P4 socket 478.
I favor [3] 470uF like I see used in Xeon server boards. - Because I'm chicken.
[ESR is more important than uF here but you do need -some- uF.]

.

The caps labeled B in this picture by the DIMM is the only one bulging for my 2 DELL's. Could added RAM have caused this?

[Jay_Slim]

Re: Dell OptiPlex GX270 - multiple bad cap failures

The caps labeled B in this picture by the DIMM is the only one bulging for my 2 DELL's. Could added RAM have caused this?

This is the picture I was referring to.

[Topcat]

Re: Dell OptiPlex GX270 - multiple bad cap failures

^
If you have the small form factor case, replace them all, even if they're Rubycon or Panasonic. The SFF cases don't breathe well at all, and I've seen rubies and pannies cook in them as well. Also crack your PSU open and take a look if you have a SFF.

For long lifespan on the motherboard, poly mod it.

[Jay_Slim]

Re: Dell OptiPlex GX270 - multiple bad cap failures

^
If you have the small form factor case, replace them all, even if they're Rubycon or Panasonic. The SFF cases don't breathe well at all, and I've seen rubies and pannies cook in them as well. Also crack your PSU open and take a look if you have a SFF.

For long lifespan on the motherboard, poly mod it.

I have 2 GX270's. One is SDT and one is SFF, both have that one cap by the DIMM and AGP slot that is bulging. All the others look okay, I know that doesn't mean they are.

You're right about the heat issues, wouldn't it be better just to stick them in aother case?

[Topcat]

Re: Dell OptiPlex GX270 - multiple bad cap failures

I have 2 GX270's. One is SDT and one is SFF, both have that one cap by the DIMM and AGP slot that is bulging. All the others look okay, I know that doesn't mean they are.

You're right about the heat issues, wouldn't it be better just to stick them in aother case?

Its been done, but the boards are proprietary to their Dell clamshell cases. Fitting them into a regular ATX case requires a little ingenuity, but it is definitely do-able. I've done it a couple times with some good boards I got that came in absolutely demolished cases. hated to waste good hardware just because the case was fubar. The came from a recycler from a corporation, and their IT guys just tossed them into gaylords (big dumpsters), and sent them to the recyclers....bastards

[lightingguy32]

Re: Dell OptiPlex GX270 - multiple bad cap failures

I can't say how many of these we have had. We have at least 100 Dell GX270 PCs at my work and plenty more GX280 machines. I've been told that the later GX270 machines switched to the motherboard used in the GX280.

I don't think that would be possible. Physically, yes it will work, but CPU socket and graphics bus wise, the GX280 is an LGA775 socket, the 270 a socket 478 and I believe that the gx280 has a PCI-Express graphics slot and the 270 an AGP.

Where I work, if anyone mentions the models GX270 (or some GX280s depending on how old they are) we reply back: Surplus them.

[kturnerga]

Re: Dell OptiPlex GX270 - multiple bad cap failures

Question; is there anybody who has seen SEVENTEEN swollen or busted caps on a GX270's motherboard. BTW one of mine had a 1500uf 6.5v cap swollen and oozing; it was the only one. I recapped it with a (thought to be) good cap and I got no video even with a good vid card. It posted fine otherwise. We have eight or so machines that have swollen caps and were short on PC's at the store so out came the soldering iron. Business will have to be VERY dead before we do recapping at the store. Just wondering if it's worth it to do ten (average failed caps in the bunch)on a board?

[Uranium-235]

Re: Dell OptiPlex GX270 - multiple bad cap failures

I just got one. I replaced all 9 of the 6.3 1800's with used 2.5 820 polys (I tested first)

and replaced the 1800 16v's with rubycons of the same (used, but tested...heh)

hit the power button *buuuuuz**pop*. two of the 1800 16's blew, leaking. replaced them with some good used sanyos, same thing, bloated in half a second, oozing capicator puss

think one of the mosfets has a short?

I know you don't approve of used caps, but I have had success with ones I test first (with multimeter, making sure resistance climbs ok). I know its kind of half-assed, but its worked before

[Scenic]

Re: Dell OptiPlex GX270 - multiple bad cap failures

^ this screams wrong polarity..

[Uranium-235]

Re: Dell OptiPlex GX270 - multiple bad cap failures

I don't think so, cause, there were 3 in paralell, and only two blew other one was fine.

but funny story from 5 minutes ago...

after reading a thread here I decided to try and recap this Asus A8N-E. I replaced all those KZG's with poly 2.5 820's, and I replaced ONE 16v 1000 with a 16 1200. I turned it on and it literally sprayed cap spooge on my arm (wasn't hot or anyting). I looked on the board, and ALL those 16v 1000's are not put on with opposite polarity from the board markings

[Scenic]

Re: Dell OptiPlex GX270 - multiple bad cap failures

asus, asrock and those dells have the positive side marked on the board, unlike all others which do it the standard way by marking the negative side..

[Uranium-235]

Re: Dell OptiPlex GX270 - multiple bad cap failures

holy crap you're right. are the mark on polys pos or neg?

[Scenic]

Re: Dell OptiPlex GX270 - multiple bad cap failures

negative on all thru-hole polys i've seen so far

btw: i also once fried a whole row (VRM of a P4 board) of shiny new pannys on a crappy asus board because i simply forgot about them being retarded and marking the positive side unlike the rest of the whole industry.. -.-!