Dell Studio XPS 8100 dead in the water

[dood]

Got a call today from a longtime customer... there was a brief power outage at her house and now her computer won't turn on. Walked her through the basics - unplug for 45 seconds and then plug back in and try again... try holding the power button down for a while, etc. No go, so I swung out and picked it up, expecting a bad PSU.

Got it home and put in my testing PSU, and I get no reaction. The orange LED on the mobo is lit, but pressing the power button results in nothing. I pulled out the video card, unhooked all the drives, and pulled all but one stick of RAM. Still nothing. Pulled the CMOS battery and unplugged the PSU for about a minute, then held down the power button for a minute... still nothing when I plugged it back in.

I plugged the Dell PSU back in with everything unhooked, and the green LED on the back doesn't light, so I'm assuming that it /is/ dead. Now I'm just wondering if it took the mobo with it.

It's been a while since I've troubleshot a hardware issue, so I figured I'd bounce it off all y'all before I give them the bad news that their PC is toast.

[stj]

Re: Dell Studio XPS 8100 dead in the water

try another cpu - they can fail.

[Compgeke]

Re: Dell Studio XPS 8100 dead in the water

It's probably the motherboard. I was given an XPS 8100 that had the exact same story, turned out to be a bad motherboard in the end. Slight difference was it'd sometimes turn on and do nothing.

[jiroy]

Re: Dell Studio XPS 8100 dead in the water

Did you measure the voltage of the CMOS battery ? .. If it is under a decent level , the bios would reset to default , and in old systems , the date will return to 19xx plus lot of other weird consequences like for instance a resulting resources conflict , hence preventing the ignition of the motherboard .

[RJARRRPCGP]

Re: Dell Studio XPS 8100 dead in the water

Did you measure the voltage of the CMOS battery ? .. If it is under a decent level , the bios would reset to default , and in old systems , the date will return to 19xx plus lot of other weird consequences like for instance a resulting resources conflict , hence preventing the ignition of the motherboard .

That doesn't cause a PSU lockout condition... It's most likely because of a transient peak in the waveform and some PSUs don't take lightly to that at all!
(I'm talking about brief blackouts, such as a 1-second blackout, especially split-second blackouts, such as a 700 ms blackout)

With some PSUs, you must unplug it and plug it back in for it to turn on!

[kaboom]

Re: Dell Studio XPS 8100 dead in the water

Pull power supply or disconnect it from all loads in machine.

Apply line voltage to supply- do you have +5VSB? If so, does main supply come on when shorting PS-ON to GND?

If no +5VSB, likely bad startup cap let go when AC was lost, and aux supply was then unable to come back when AC came back. Typical with cheapos/ltecs/etc. Unit was working til AC was lost because the aux supply "kickstarted" itself months/years ago, before AC failure. Meanwhile, startup/aux caps for the +5VBS supply were going bad all the while- you just don't know this til you lose AC power.

If you have +5VSB, but main supply won't come up, check aux filter/startup caps for the main supply instead. Dell and cheapo/ltec/ost are like "hotdogs and mustard."

If you have output on supposedly +5VSB output, is it 5V, or did it "run away?"



Are there any '03-'05 HM or HN (likely leaked by now) caps on the input or output of the CPU regulator?

[dmill89]

Re: Dell Studio XPS 8100 dead in the water

Are there any '03-'05 HM or HN (likely leaked by now) caps on the input or output of the CPU regulator?

Considering a Studio XPS 8100 is a circa-2010 first-gen I5/I7 system I would certainly hope it doesn't have any 03-05 date code caps in it. It may however have chemi-con KZG/KZJ which also have known issues and were common in Dells (and many other brands) from that time period. PSU is definitely a prime suspect, I believe these systems use a standard ATX PSU and only a 350w, so it shouldn't be too difficult to find something that will work with it. Do you have an extra PSU (or one you can barrow from another system) to test it with, that could probably either confirm or rule out a dead PSU pretty quickly. If it still doesn't work with a known working PSU then the motherboard becomes the prime suspect.

[kaboom]

Re: Dell Studio XPS 8100 dead in the water

Looks like I mentioned the '03-'05 HM/HN caps "by habit," without checking how old that system is...

[jiroy]

Re: Dell Studio XPS 8100 dead in the water

That doesn't cause a PSU lockout condition... It's most likely because of a transient peak in the waveform and some PSUs don't take lightly to that at all!
(I'm talking about brief blackouts, such as a 1-second blackout, especially split-second blackouts, such as a 700 ms blackout)

With some PSUs, you must unplug it and plug it back in for it to turn on!

He said he used his testing PSU , so issues in the PSU has become irrelevant .
Next logical steps is to test a shorted battery or an outdated one . Since i assumed he didn't unplug any attached components , then yes , some mobos , when bios is reset , can do a non ignition state .
I had once one dead LG laptop for repair , and usually i ask the customer about how and when . He said the laptop felt from the washing machine due to vibration . So logically , i was looking for cracks . After disassembling the whole unit , i find out one leg of the cmos battery in the air , i soldered it and the LG went on .