Dell GX620

[Topcat]

Re: Dell GX620

^
You must be the capking guy... haha

I have some 620's and some 280's in the shop, I'll try to get a better comparative photograph.

[PCTechNY23]

Re: Dell GX620

This would make more sense if I included the link: http://www.flickr.com/photos/43646305@N04/4018780162/

[PCTechNY23]

Re: Dell GX620

Here is a not very good side by side ( GX620XSX280 ) but it would make a great nerd edition photohunt screen. These boards will both fit on the same tray and into each others case. Aside from a chip switch, led upgrade, Chipset heat sync upgrade ( those retaining clips are prone to pop off the board when they get hot), and a couple cap substitutions ( the 2200 next to the battery to a 16v 220uF, 1 extra 16v 1000uF filling a blank, 3 extra 6.3v 1800uFs filling blanks on the left of the heat sync, and leaves a blank next to the printer port), the SX280 is identical to the GX620as far as I can see. I am sure I missed something and it will be pointed out but as far as trends I have noticed on the SX280 I expect them to transfer to the GX620. The optiplex 745 does have a fan under the hard drive and I will let you know next week if the fans can be fitted to the GX620 and SX280. I borrowed the pics from thecapking.com, hopefully he won't mind.

[Topcat]

Re: Dell GX620

So I understand the GX620 [I don't have one to play with yet but I'm looking] puts a bunch of 220uF right under the hard drive which limits airflow and is source of heat on the 220uF that SX270/SX280 don't have.

The SX280 and GX620 are almost IDENTICAL systems, only a few variations in their boards, cases are identical. The 220uf caps don't fail on them, its the little 22uF 25v caps that will go from time to time. The SX270, I've never seen anything lower than the 680uF caps fail on.

FWIW on the sx280 and gx620, I've stuck 220uF 16v caps in place of the failed 22uF 25v caps many times, never had any problems doing that.

[PCTechNY23]

Re: Dell GX620

Still trying to wrap my head around this one

"So I understand the GX620 [I don't have one to play with yet but I'm looking] puts a bunch of 220uF right under the hard drive which limits airflow and is source of heat on the 220uF that SX270/SX280 don't have."

Are you saying the SX270/SX280 do not have hard drives?

[PCTechNY23]

Re: Dell GX620

The SX280 DO have at least 8X 16v 220uFs under the hard drive, the ones I have seen are Rubycon YK

The GX620 USFF has 11 16v 220uFs under the hard drive and those have been chemi-con SMG series on the machines I have seen so far.

Look at the picture:
http://www.flickr.com/photos/3082593...n/photostream/

Full list of GX620 USFF caps from the cap king:
7X 6.3v 2200uF
13X 6.3v 1800uF
5X 6.3v 820uF
4X 16v 1000uF
3X 16v 1500uF
19X 16v 220uF
4X 25v 22uF

[PCBONEZ]

Re: Dell GX620

The only thing unique about midibob's post is that he's one of the few that understands the whole problem.
Most techs are so 'conditioned' as to what to replace they don't look around for odd problems.
I suspect a lot of repairable GX620 boards are getting written off and trashed because the techs don't think to check the 220uF [or even 100uF].
-
Absolutely not a fluke.
Not uncommon for 85c caps to dry out or bloat on a mobo with poor airflow.
Thing is they aren't heavily loaded with ripple like the 'popular' replacement caps so it [usually] takes them longer to dry or bloat and cause problems.
-
So I understand the GX620 [I don't have one to play with yet but I'm looking] puts a bunch of 220uF right under the hard drive which limits airflow and is source of heat on the 220uF that SX270/SX280 don't have.

Personally if it's USFF or a server board [or for ME] and it has 85c caps I replace them.
Buying in bulk [100pc+] the cost difference is usually < $3 per board [for Dell GX/SX anyway] and that's cheap insurance.
- It's also handy to have a handful of 100uF and 220uF around to replace 85c caps in LCD screens when they show up so I just keep at least ~50pc of those sizes in stock now.
.

[PCTechNY23]

Re: Dell GX620

I saw the post and asked the stupid question because I figured midibob may have had a unique situation or possibly just a fluke. These board are almost identical to the SX280s that I have been doing a lot of since our Dell warranty ran out ( my recaps last longer than their child labor ones anyway ) and I never had a problem with the 16v 220uFs 85c on those. That coupled with the fact that I looked at every board replaced by Dell techs and I didn't see any blown 16v 220uFs I am somewhat surprised. Now that our warranty is up on most of these and our asset manager will finally let me take a crack at them I will have to test some of the 16v 220uFs and let you know what I find.

[PCBONEZ]

Re: Dell GX620

Dunno if you can see it but there it is.
They are noticeably plumped up [bulged] between the lines of the vent stamp.
Obvious / easy to see in person. - Hard to show in a photo.

The one showing the RAM slots is the D850GB.
The Kittyhawk is the other one.

[PCBONEZ]

Re: Dell GX620

Oops, my mistake.
The bloated caps on both those are 85c 100uF 25v 6.3mm.
100% on the D850GB and ~50% on the Gateway.
Gateway also has 2 or 3 85c 5mm [no vents] that -might- be bloated.

I'll try to get a snap-shot but bloated 6.3mm don't show up well.
- They don't have -room- to bloat that much when they do bloat so the 'bump' is slight.

[PCBONEZ]

Re: Dell GX620

Read the quote in my last post.
[Which was quoted right from this thread.]

I put it there so you wouldn't have to ask that question.

Personally I've seen them go bad on Intel boards all the way back to Socket 370.
[Not even 'built for Dell' Intel boards, any Intel board]
Usually happens when the fan and vents are clogged full of crap to the system isn't getting cooled.
I have an Intel D850GB [Retail version, P4 socket 423] and an Intel Kittyhawk [OEM'ed to Gateway, socket 370] in the shop right now.
- On both of them about 1/2 the 85c 220uF 16v are actually bloated.
.

[PCTechNY23]

Re: Dell GX620

Have you seen any 16v 220uFs go bad? It wouldn't surprise me if the ones under the hard drive do go I just haven't seen any on the 20 boards we got replaced by Dell. I did see a couple bulging 25v 22uFs.

[PCBONEZ]

Re: Dell GX620

I was talking about 'that other guy'.

I expected GX620 to 'get popular' on the re-cap front eventually.

Maybe eventually someone will come up with a CD bay module for Optiplex with a metal tray that can be used to toast bread or bake personal pizzas.
.

[Topcat]

Re: Dell GX620

Problem is he doesn't supply the 220uF and on GX620 those go too.

I do have 220uF caps now, and a kit for the GX620 is coming soon, I'm starting to really see a lot of these.

https://www.badcaps.net/pages.php?vid=22

[PCBONEZ]

Re: Dell GX620

Problem is he doesn't supply the 220uF and on GX620 those go too.

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.

[PCTechNY23]

Re: Dell GX620

I was able to find pictures/list of the GX620 USFF caps here:

http://www.flickr.com/photos/30825931@N06/4011932129/

http://www.flickr.com/photos/3082593...n/photostream/

The Cap King has the kits for $19 shipped.

[midibob]

Re: Dell GX620

Hi Lagacy,

I would think if it's anything like the 620's then 85c rated caps won't last very long. Dell used 85c for the smaller valued ones and they nearly all go high ESR. The big boys, 1000uf etc will probably vent after a short while. They used to at 105c after a couple of years!!

Midibob

[lagacy]

Re: Dell GX620

Hi all
I have just got a used mobo Dell Optiplex 755. The mobo code is OGM819-13740 assembled in China. Two capacitors have been replaced by Nichicon 1000uF-85oC. They are C667 near internal spk socket and C502 b/w the CPU and the North bridge. I would appreciate if you could help me with the exact value of the capacitors which have been replaced.
Thank you
Lagacy

[lightingguy32]

Re: Dell GX620

What I encountered over the summer is that many of the GX620s that we have reimaged have been tagged as having their power supply units replaced. Also from reading online, there seems to be a problem with several caps in the GX 620 PSU that dell has not acknowledged, though from reading I can gather thousands of units (mostly the minitower psu (305w) and desktop PSU) are affected.

[PCBONEZ]

Re: Dell GX620

Probably Not.
New machine may have same or a new problem.
-
Learn to solder and then you can fix it for less than lunch costs.