Badcaps.net Forum
Go Back   Badcaps Forums > Motherboards with Bad Capacitors > Major Manufacturers Boards
Register FAQ Calendar Search Today's Posts Mark Forums Read

View Poll Results: Have you seen or experienced a cap-related motherboard failure on a Dell system?
Yes 175 86.21%
No 28 13.79%
Voters: 203. You may not vote on this poll

 
Thread Tools Display Modes
Old 02-11-2011, 11:10 AM   #221
Uranium-235
Muffins
 
Uranium-235's Avatar
 
Join Date: Aug 2007
City & State: tehas
My Country: US
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 3,164
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

well I got them all reversed, and it almost comes on, but never fully goes on

I tried, the mofsets might be burned out. oh well plan b
Uranium-235 is offline   Reply With Quote
Old 02-11-2011, 01:02 PM   #222
Uranium-235
Muffins
 
Uranium-235's Avatar
 
Join Date: Aug 2007
City & State: tehas
My Country: US
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 3,164
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

well, plan b was about to rock, and I f*cked it up

I got a dimension 4600c from work, it boots up to say "northbridge heatsink not found, halting"

one of the metal loops that holds the nb heatsink on broke, I'd imagine just soldering a wire on and using it to hold the nb heatsink hook would work

I was also going to replace some KGZ's on the VRM (rest of them Sanyos, which are OK). I had to take the P4 mount off, and it was being sooo stubbron, I actually cut the plastic pushers off and force it off, and mount the P4 holder from the gx270 (which uses screws). I folded a static bag to protect the board when I pryd the mount off, but I didn't fold it enough. it broke 3 traces between the cpu and nb, and the thing won't power on now. I tried to scrape some insulation off some of those traces to get a wire bypassing the broken traces but it just isn't working

damnit
Uranium-235 is offline   Reply With Quote
Old 02-11-2011, 03:08 PM   #223
Uranium-235
Muffins
 
Uranium-235's Avatar
 
Join Date: Aug 2007
City & State: tehas
My Country: US
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 3,164
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

well I just replaced all those polys with lytics and it does the same thing, never fully comes on then dies. what do you think it is? mosfets?
Uranium-235 is offline   Reply With Quote
Old 09-06-2011, 05:12 PM   #224
tuskenrader
Joe Rader
 
tuskenrader's Avatar
 
Join Date: May 2011
City & State: West-Central Minnesota
Posts: 7
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

I know it's been half a year since this thread seemed to die, but just thought I'd throw out a question here. There's one 680uF 10v cap which BadCaps says can be replaced with an 820uF 6.3v on its GX270 kit page. I just wanted to confirm that here on the forum. Going down in voltage makes me wary.
tuskenrader is offline   Reply With Quote
Old 09-06-2011, 08:09 PM   #225
PCBONEZ
Grumpy Old Fart
 
PCBONEZ's Avatar
 
Join Date: Aug 2005
City & State: Phoenix, AZ
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Professional Tech
Posts: 10,631
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

I use a 680uF, reason being those boards have 820's all over them so if an 820 was a good idea they'd just use one in the first place to reduce their costs.
And it's the same situation with that one 680uF in the same place on many Dell boards.
Obviously the uF matters on that one cap.

I tried to trace the circuit at one point.
It has something to do with the chipset but I couldn't ID the specific pin.
.
__________________
Mann-Made Global Warming.
- We should be more concerned about the Intellectual Climate.

-
Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.

- Dr Seuss
-
You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
-
PCBONEZ is offline   Reply With Quote
Old 09-06-2011, 10:54 PM   #226
brethin
Badcaps Veteran
 
Join Date: Dec 2008
City & State: Owensboro, KY.
My Country: USA
Line Voltage: 120VAC 60Hz
I'm a: Professional Tech
Posts: 1,673
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

I dont think he was questioning the uF change from 680uF to 820uF but was questioning the voltage change from 10v to 6.3v. Not personaly knowing the circuit myself I would say if Topcat has it listed as a replacement it is a safe replacememnt. I am sure he has done his homework and didnt just use the new value just to change it.
brethin is offline   Reply With Quote
Old 09-07-2011, 06:56 AM   #227
PCBONEZ
Grumpy Old Fart
 
PCBONEZ's Avatar
 
Join Date: Aug 2005
City & State: Phoenix, AZ
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Professional Tech
Posts: 10,631
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

Quote:
Originally Posted by brethin View Post
I dont think he was questioning the uF change from 680uF to 820uF but was questioning the voltage change from 10v to 6.3v.
The voltage change is fine.
I don't have my notes handy but I do remember it's on less than 5v.

Quote:
Originally Posted by brethin View Post
Not personaly knowing the circuit myself I would say if Topcat has it listed as a replacement it is a safe replacememnt. I am sure he has done his homework and didnt just use the new value just to change it.
Doubtful. - The methodology has been stated before.
The odd way Intel sticks solidly to 680uF on multiple Dell boards for that one cap when 820uF in the same diameter are stocked in droves indicates that particular circuit it is frequency sensitive and TC's method doesn't look for that. It's associated with the chipset so it might only have to do with sound but OTOH it might have to do with syncing the clocks between the CPU and RAM. To check for problems with the latter you'd have to actually count RAM errors at the chipset [vice at the RAM] which you can't do with normal equipment or software.
That situation is pretty rare. It's not something people think of.
.
Now, if I only saw the peculiar use of a 680uF in place of readily available 820uF's they buy in mass quantities on one model board I wouldn't think too much of it but Intel does it on multiple models with similar chipsets through the socket 478 and 775 models so for some reason the value for that particular cap is important.
And I think Intel has probably "done it's homework" too and they didn't just randomly use an odd value and then stick to it with such enthusiasm on dozens of models if the value didn't matter.
.

Last edited by PCBONEZ; 09-07-2011 at 08:07 AM..
PCBONEZ is offline   Reply With Quote
Old 09-07-2011, 01:24 PM   #228
tuskenrader
Joe Rader
 
tuskenrader's Avatar
 
Join Date: May 2011
City & State: West-Central Minnesota
Posts: 7
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

Good to hear that the voltage won't be a problem. If it's less than 5v, then I feel comfortable with a 6.3v cap. As far as the uF goes, moving to an 820uF is about +20.59% over the 680uF value. If the +-20% rule can be trusted in most cases I guess I can buy TC's decision to stick a 820uF there. I'll give it a shot on one I've already replaced and see if I run into troubles. But I think I will be buying a small baggie of 680uF's, though. I was hoping my big bag of 820uF's would suffice since I already have them, but no biggie. I really appreciate everyone's input!
tuskenrader is offline   Reply With Quote
Old 09-07-2011, 01:34 PM   #229
tuskenrader
Joe Rader
 
tuskenrader's Avatar
 
Join Date: May 2011
City & State: West-Central Minnesota
Posts: 7
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

Just got a response from the man in charge. The kit page needed updating and he now is always including the 680uF in the GX270 kit. He also said that you can always drop a 10v cap down to a 6.3v since they always run at 5v on any board. Very interesting. I asked him if he thought 820uF would work.
tuskenrader is offline   Reply With Quote
Old 09-07-2011, 02:29 PM   #230
PCBONEZ
Grumpy Old Fart
 
PCBONEZ's Avatar
 
Join Date: Aug 2005
City & State: Phoenix, AZ
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Professional Tech
Posts: 10,631
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

Quote:
Originally Posted by tuskenrader View Post
The kit page needed updating and he now is always including the 680uF in the GX270 kit.
Probably happened after an old thread where I pointed out how weird it was for Intel to stick to using a 680uF there.

I really suspect 680uF is already pushing the upper design limits for that cap.
[As in Intel pushed it as far as they could.]
That cap is blown on some where between 1/4 and 1/2 the [maybe 1/3] of the Dell boards I see, even when few other caps are blown. That suggests to me that it's heavily loaded. The fact they didn't use an 820uF there for the bigger can [to up the ripple rating] tells me they can't in that spot for some reason.
.
PCBONEZ is offline   Reply With Quote
Old 02-15-2012, 08:10 AM   #231
Gabriel
Badcaps Veteran
 
Join Date: Jan 2010
City & State: Northern Norway
My Country: Norway
Line Voltage: 230VAC 50Hz
I'm a: Knowledge Seeker
Posts: 360
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

Is it possible to use a gx280 psu on a gx270 mb ?

I guess the 280 psu has more wattage and they look alike but are they interchangeable ?
Gabriel is offline   Reply With Quote
Old 02-15-2012, 08:33 PM   #232
severach
Badcaps Veteran
 
Join Date: Aug 2007
City & State: Michigan
My Country: USA
Line Voltage: 120VAC 60Hz
I'm a: Hobbyist Tech
Posts: 982
Default Re: Dell OptiPlex GX270 - multiple bad cap failures

GX280 tower PSU: 24 pin
GX270 tower PSU: 20 pin

The desktop and slim desktop PSU are both 20 pin with SATA power for GX280 and Molex power for GX270. It works if you can find a way to power the hard drive.

20 and 24 pin supplies are compatible if there is no physical obstruction to plugging it in.
severach is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2019
Powered by vBulletin ®
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 08:25 AM.
Did you find this forum helpful?