Dell GX620

[BarryS]

Re: Dell GX620

Have just had capacitor c402 fail on a 620 usff, Dell want 250GBP to replace, will be cheaper to buy a newer machine with a longer warranty.

[computernut]

Re: Dell GX620

Yep!! I think we are just seeing the tip of an iceberg on these cooking CAPs. I just wish someone would come out with a kit and offer install. But maybe there is not enough gone bad yet.
I have had 3 go belly up and bought motherboards from http://www.cygnussupply.com They have excellent service!! I bought the refurbished because they are less expensive and all 3 motherboards worked great. Just be sure to order the right ones. Be sure to check the motherboard for the part number. Mine was
U8811 Dell System Board ( Motherboard ) w/Tempan, OptiPlex GX620, USFF Yours may be different.

[drueter]

Re: Dell GX620

I can confirm that the Dell GX620 motherboards do develop a problem with capacitors. Specific symptoms, from my personal experience:

• System becomes unstable / locks up periodically (1-2 times per day)
• Event log shows hard drive controller errors: Source: Disk / Event ID: 11 / The driver detected a controller error on \Device\Harddisk0\D
• Hard drive controller errors reported EVEN ON NEW PCI SATA CONTROLLER--not just the on-board controller!
• Hard drive transfer mode is degraded from DMA to PIO--which is MUCH slower, and causes other problems
• USB gets flakey, such as: USB keyboard / mouse go unresponsive, even though system can still be accessed remotely via RDP
• USB gets flakey, such as: USB-attached hard drives spontaneously disconnect / have delayed write failures, etc.

On my board, there were 4 capacitors that exhibited visible signs of deterioration: bulging caps and corrosion. (3 were 2200 mf and 1 was 1800 mf). Others may be failing too--those were the only ones with visible indication of problems.

My system was purchased July 24, 2005--and began having noticeable problems about June of 2009--almost 4 years to the day. (System used as main workstation / daily use / powered on 24 x 7. Replaced power supply once due to failed fan, had been running 4 gig of ram and Seagate 320 gig Barracuda drive.)

See attachment for photo of capacitors on my board.

I spent many hours slogging through these system problems before replacing the motherboard. A motherboard failure seemed unlikely to me--especially because the system still ran. In my case the symptoms got progressively worse over a period of several weeks. But swapping out the motherboard resolved all of these problems.

I hadn't heard of the capacitor problem before. Thanks badcaps.net for the information here!

[midibob]

Re: Dell GX620

A point to note on these boards is not to forget the 220uF caps. Although they don't blow like their larger cousins they do dry out and I have had many instances of them being high ESR to completely open circuit.

Bob

[PCBONEZ]

Re: Dell GX620

GX620 have heat issues due to poor air flow design.
There is another thread on them in here somewhere.
-
If you want them to last longer the second time around the best thing to do is work out a polymer upgrade for the boards. Cost will probably be 2x to 3x that of using electrolytic caps but the odds are you won't have to recap again later and with lytics you likely will have to.
You will have to [should] take voltage readings on the caps you are replacing because it's common to use 6.3v lytics on small voltages like 1.5v-3.3v and with poly you can use lower voltage caps. [2.5v and 4v poly are much less expensive tha 6.3v poly. - But you HAVE to make sure the caps voltage rating is the same or more than the actual circuit voltage. For example don't use a 4v cap on a 5v circuit.]
-
You could also try it improve the air flow but you need to drill some air vent holes in strategic locations [dead flow areas] and that might not 'look to pretty' to people that lift their pinky when they sip coffee/tea.
.

[370forlife]

Re: Dell GX620

https://www.badcaps.net/pages.php?vid=15

That is what you should fill out, but remember that he is usually pretty busy.

[computernut]

Re: Dell GX620

Do you know of anyone doing the re-capping. I don't know if I want to try it or not. I has been ages since I have done serious soldering. I put in a request to Chris at "Administrator" <admin@badcaps.net>
but have not heard anything back yet.

[370forlife]

Re: Dell GX620

God those things must get really cooking in order to blow out rubys.

You should recap without processor, ram, etc... in it. Though a few people have done it with processor in with success.

[computernut]

Re: Dell GX620

New to the forum:
I have 7 Dell GX620 USFF computers in the network. They are all just out of warranty. 3 of the 7 have had the caps blow. I have replaced the moboards in all 3 so far. So I have 3 moboards I want to get recaped.
Question Can they be capped without the Processor and memory on the board and be sure they will work? The reason for that is that the computers are in use in a business enviroment.
I have included Pic's of the motherboards and put a red dot on each cap that show signs of leakage and/or bulging. The first two computers would not even start. The last computer would post but hang up and give the message that there was no boot drive.

Thanks
Chet

[midibob]

Re: Dell GX620

Out of interest I've just been told that the newer GX750's now have a small fan attached to the underside of the hard disk carrier. How far this will go to stop the caps suffering remains to be seen.
Obviously Del have taken note of the 620 failures!

Bob

[sargeslaughter]

Re: Dell GX620

I am the network administrator of a 60 node network and Yes the ultra small form factor Optiplex GX 620's have a very high rate of failure. In October of 2008 I had about 40 + of 60 that were failing all in the same month. I had dell replace every one of them. During the replacement, there was an occasional bad board right out of the box. Don't they test these things? Occasionally they'll give you a bum board that never was retro fitted with the new caps. I had one go bad today. Sure enough it has the old style caps with the Y instead of the K design and it is leaking.

[midibob]

Re: Dell GX620

Hi,

I believe these are the USFF type as they have the external PSU brick.

Out of interest they are still trickling in and almost all with the same caps going bad. No repaired ones have bounced yet, touch wood, but lets see what summertime brings.

I find it strange that at the failure rate of these boards, there hasn't been more
people here having the same problems?

Bob

[lightingguy32]

Re: Dell GX620

What form factor are those GX620 machines? I work as a volunteer computer tech for both a local university (which has hundreds of GX620s all mini tower) and my high school (which has about 200 some GX620 desktop form factor machines)

[midibob]

Re: Dell GX620

A quick update on the 620's.

The failed boards are still trickling in and the common fault in almost all cases bar one is the two 820uF venting (under the disk drive) and all the 220uF around the same area and close to the regulators.
Interestingly enough the odd one I've just repaired, the usual two 820uF tested fine and the failure was due to the numerous 220uF caps going bad. Something to watch out for I think as one usually goes straight for the high value caps.

All the other caps on the board were tested and proved to be at 0.01 ohms. I did change the 820's just in case but it's odd why these haven't failed in this particular board?
I'm expecting another load of faulty boards today so I'll check the date stamps on the caps to see if anything there shows up.

I've also got a load of GX280's to repair but that's for another thread I think.

Happy New Year to all and have a good re-capping 2009

Bob

[midibob]

Re: Dell GX620

I'm keeping a database of the serial numbers as I do them with the caps that were changed. Being as the boards are now 3 years old it's doubtful the PC's will be kept for more than another two years so if they last that long then it's not a problem.
I'll certainly report back here if there's any news.

Bob

[kc8adu]

Re: Dell GX620

that board will be a good test of the samxon caps.
i am convinced that nothing short of polys will last in dell gx/sx boxes.
i just curbshopped a 280 yesterday.panasonic fj and fl blown up.
its going full poly tonight if i feel up to it.
hope you can keep that 620 to monitor the samxons.
for a fair test finish the recap as tc said.

[midibob]

Re: Dell GX620

Hi all,

Well I have to start with a loud shout of 'Geronimo' as I now have a working board.
What I've found is the 220uF caps were all going low capacitance and only being rated at 85c I'm not surprised. The ones around the outside of the board were not too bad (0.7) but the middle ones varied from ESR's of open circuit, 70, 40, 12 ohms etc. I therefore decided to replace all of them with 105c.
I replaced the two vented 820uF and out of interest they measured around 6 ohms.
All the other caps were still measuring 0.1 so for now I've decided to leave them and see how it goes. Possibly short sighted I know but checking two boards now it appears they don't suffer the same stress.

Anyway, I must give a big, big thanks to Joe (Big Pope) for sending me the caps so quickly.

As for Dell fitting 85c caps in these boards is no more than built in obsolescence and these will probably be failing in huge numbers pretty soon.
I feel a recall coming on

Thanks to all
Bob

[Topcat]

Re: Dell GX620

I've managed to get hold of another faulty board this time with with 2 blown caps on it. These are both 820uF and as you can see from attached (hopefully) photo they have blown their tops. One is next to the battery and blue link and the other to the left of the spiked ally heat sink.

Interesting thing is the caps next to them are 220uF and showing no signs of distress, but only 85c rated. These will need checking of course but how much internal heat would the 820's be generating to blow like that. I'm not convinced (yet) that this is caused by external heating alone.
Still, early days yet I suppose.

Bob

Replace everything on that board 820 and up. They're all Nichicon's. The blown 820uF's are rubycon. not uncommon for rubycons or panasonics to blow on these boards, they overheat.

[PCBONEZ]

Re: Dell GX620

The 220uF probably don't do much filtering compared to the 820's.
In fact probably aren't filter caps at all but are for coupling or something.

Recommend replacing 820's with some that handle more ripple.
The ripple capacity (kinda, sorta) tells you how much internally generated heat they can handle. More is better.

.

[midibob]

Re: Dell GX620

I've managed to get hold of another faulty board this time with with 2 blown caps on it. These are both 820uF and as you can see from attached (hopefully) photo they have blown their tops. One is next to the battery and blue link and the other to the left of the spiked ally heat sink.

Interesting thing is the caps next to them are 220uF and showing no signs of distress, but only 85c rated. These will need checking of course but how much internal heat would the 820's be generating to blow like that. I'm not convinced (yet) that this is caused by external heating alone.
Still, early days yet I suppose.

Bob