Dell Optiplex GX270 -- Nasty surprises after success

[Oerg866]

Hey!

Three GX270

ALL with failed caps

All got recapped by me

all not working correctly...

First board: ALL caps in the row behind the heatsink leaking. 3 other caps leaking.

Replaced them all. -> Board would not turn on. Turns out if one of the caps was installed, that rail shorted. Hooked it up using wires -> Works not!

Tedious hours of testing later -- broken trace found, fixed and hey presto: Works! A nice 3.2GHZ HT even.

But then, surprise surprise: The southbridge cooked itself. Why? I don't know. The caps are all good though.

==> FAIL, board complete trash, scrapped for parts (got my caps back, CPU too and also:the beeper, jumpers, battery socket, I use those to make small devices with )

Second board: 4 bad caps in the row, 2 caps near RAM slot, 1 cap near USB connectors.

Replaced them. -> Board would turn on fine! But then, I tried connecting a keyboard. It would not accept any keyboard. DARN THIS FUCKING THING

==> FAIL, board trashed for parts CPU etc.

Third board: Actually, only three bad caps on this one.

Replaced them. -> Board turns on! God I'm so happy. Accepts keyboard and everything and the southbridge is not cooking itself anytime soon it seems!

Oh well, lets turn it off and get some components to put inside. Hold on let me get this hard disk, yeah thats good it's installed there and hooked up. Let me get that XP CD out of my drawer here, alright, and let's turn this sucker on and get it to work!

Oh I am ever too optimistic. Of course it does not work how I expected. Plugged it in and: Fans start running and a constant yellow LED on the button. Aw crap. Let's google what that means.

Power issue? Oh it must be that I accidentally dropped some metal in it. Wait no it's completely clean. What the heck?

Took it out for another bench test. What the heck. It works?

Oh wait, no it only works some times. Oh, I get it so you're teasing me, bastard! Oh well, as soon as it turned on I proceeded with an XP install. No issues AT ALL there. Shut it down to burn a CD with drivers but oops. TURN ON YOU PIECE OF SHIT.

Ah there we go. Well but first I'm going to do some testing. Ah yes there we go Prime95. Fan goes faster now, so that's working. Went to my brother's place to have some lunch and play some video games. Came back -- yeah it's still running just fine. Tried some FurMark to test the GFX card (I put in a low profile GF6200 -- Oh wow, not even one frame per second. But hey, it's not crashing.

So I got ~6 hours of Prime95 and ~3 Hours of Furmark and nothing crashed.

Can anyone tell me what the hell is going on with this? It works just fine but only sometimes it turns on

cheers!

[seanc]

Re: Dell Optiplex GX270 -- Nasty surprises after success

1. Caps are backwards - remember the silkscreens on Dell and ASUS boards mean that white stripe = positive, but I suspect you would have noticed by now.
2. You have 3 failed power supply units, or you are testing all with one failed power supply unit.

I had 2 x GX270 humming away nicely, both boards were replaced by Dell in 2007, one has subsequently had the caps next to the CPU replaced since they were '03 dated and one was leaking.

I have 2 x broken/funky GX270 at work. One with a known bad PSU and mobo, the other is just funky, sometimes works, sometimes not and I've not investigated into the cause, probably the PSU.

[Oerg866]

Re: Dell Optiplex GX270 -- Nasty surprises after success

1. Caps are backwards - remember the silkscreens on Dell and ASUS boards mean that white stripe = positive, but I suspect you would have noticed by now.
2. You have 3 failed power supply units, or you are testing all with one failed power supply unit.

I had 2 x GX270 humming away nicely, both boards were replaced by Dell in 2007, one has subsequently had the caps next to the CPU replaced since they were '03 dated and one was leaking.

I have 2 x broken/funky GX270 at work. One with a known bad PSU and mobo, the other is just funky, sometimes works, sometimes not and I've not investigated into the cause, probably the PSU.

1. Yes, I noticed that right off the bat, thanks for the hint though
2. Nope. My Benchtest recapped FSP 300W and my 350W FSP both had same effect like DELL PSUs.

thanks for the fast answer!

Cheers,
Oerg866

[seanc]

Re: Dell Optiplex GX270 -- Nasty surprises after success

What caps are you using as replacements?

Board 1 - well it's fried now.
Board 2 - reset CMOS? More bad caps?
Board 3 - bad solder joints, more bad caps.

I remember the caps next to the RAM liked to fail, others have probably dried out. One of the dead ones at work has a bad cap slap bang in the middle of the board - Panasonic I believe too. I very much suspect that's a result of the failed PSU though.

[Oerg866]

Re: Dell Optiplex GX270 -- Nasty surprises after success

Board 2: Replaced all caps, no luck.

Board 3: OK whenever my soldering iron is working again (I need to let it dry because I accidentally made water drop into it... long story) I will replace all remaining caps.

Cheers !!

[Scenic]

Re: Dell Optiplex GX270 -- Nasty surprises after success

as i know oerg from another forum, i suspect crappy/generic caps (probably from junk boards) soldered in with a crappy excuse of a soldering iron with cold joints, destroyed thru-holes and everything..

[mockingbird]

Re: Dell Optiplex GX270 -- Nasty surprises after success

Yea, if you rip off the pads by getting overnaxious and forcing the leads through the holes, you will have problems.

[Oerg866]

Re: Dell Optiplex GX270 -- Nasty surprises after success

as i know oerg from another forum, i suspect crappy/generic caps (probably from junk boards) soldered in with a crappy excuse of a soldering iron with cold joints, destroyed thru-holes and everything..

Ha ha

1. why is a cheap shot like this necessary? I know you aswell from there and honestly you don't seem to be in any position to do so. (Also what the hell are you talking about?)

2. The capacitors are all from Rubycon. MBZ and YXG.

3. I double checked that the joints are not cold.

4. I request a moderator delete the above post. I am not stupid.