Whoah... no POST... how to diagnose?

[Coyote]

Halp!

Anybody know how to diagnose a faulty PSU? I did a bit of upgrading to my rig this week (my old specs are here: http://www.h-townmadness.com/forum/s...13&postcount=8) whereby I swapped out my eVGA 8800 GTS SLi cards for 2 shiny new GTX 260 (also eVGA) in SLi. On Thursday, I was back up and running with Linux and WinXP 64 with the new configuration. On Friday, I put it through its paces with a few hours of Crysis with everything on High (no DX10 in WinXP...) and 16xQ AA turned on. It was BEAUTIFUL and still averaged more than 25 fps. I had also enabled SpeedStep in my BIOS since I figured if the GTX 260s were going to throttle back when not in use, I might as well do that with my cores, right?

After cooking my GPUs for a few hours, I turned it off to go to bed and when I tried to turn it on this evening, it only powered on for 2-3 seconds and then shut down. WTF?!?!? I've tried resetting the CMOS and pulling the GTX cards out but my machine just doesn't want to POST. The crazy thing is that it was working great until I powered it off for the night. So... the question now is to determine whodunnit...

- Was it the GTX twins with thermal expansion? One of the cards reportedly hit 92C during my Crysis bender...

- Was the PSU cracking under the needs of the new GPUs?

- Was it the CPU borking out after I enabled SpeedStep?

The problem, of course, is that while I don't know the culprit, I also don't know the victim! I don't know what actually died.

Anybody have any similar issues with machines not POSTing like this? Does this sound like a CPU issue? Or maybe it's a bad mobo now? Whaddya think?

[HTM|Assraker]

I have a power supply checker for diagnostics.

http://www.directron.com/ps124.html

Unless you have a good bit of electrical knowledge as well as a decent volt meter, I recommend getting one.

There are 3 possibilities here:
CPU is cooked
PS is cooked
MB is cooked. <<least likely

If you have a spare PS you can swap it out to do a simple check, that would at least rule out the PS if you do not have a diagnostic tool.

[HTM|Minion]

Maybe this will help? I'd be more helpful if I wasn't falling asleep. -

http://www.daileyint.com/hmdpc/manual.htm

[Freak]

Read several bad reviews on the psu,lasting only 2-4 months.

[HTM~CheeZmonZter]

I have one of those PSU testers, They are awesome, Have been really happy with the purchase, Mine came from Frozen CPU, but I'm sure that they're all the same testers repackaged

My thoughts would be the PSU 1st as well......

[HTM|Minion]

Yes, it seems quality power supplies are getting harder and harder to find. Even the brands that used to be trustworthy have seen a dip in quality the last few years. I think it's due to the demand for higher wattage needs, almost as if they have increased power output without revising the heat dissipation and circuitry to handle the extra load.

[HTM~CheeZmonZter]

http://www.pcpower.com/index.html

They Use em in the Maximum PC computers, nothing else.....

[HTM|Assraker]

Enermax, ftw... Good rule of thumb, if it weighs like a brick, it should have decent heat dissipation.

[HTM~ZenEye]

This Tagan ITZ 800w seems to power my crossfire nicely

[Freak]

Quality control with stringent testing would be nice,especially with the complaints the 12v rail are coming in closer to 10v.

[Coyote]

Thanks for the link to the tester, Assraker! I'm going to order one ASAP and have it shipped overnight. EDIT: WHOAH... never mind. I'm not THAT eager to diagnose the problem that I'm willing to spend $60-70 on this tester.

You guys are right about the trying to find a good PSU. No matter what PSU I look at, I can find reviews that it's a-okay and reviews that it bricks itself. The thing has been rock solid on my older 8800 GTS setup for almost a year. So that suggests that PSUs are only good until around 70% capacity or something after which it's a game of Russian Roulette to see if it croaks.

I'll report as soon as I get the tester. Gawd, this could NOT have come at a worse time. I've got a huge project deliverable this week and next and this machine was going to be where I was going to do my 3D renderings when I was home. I guess I'll be staying a lot more at work for the next few weeks.

[HTM~Night_Ranger]

I just went through a similar problem last week. I thought the psu was giving up on me a couple of weeks ago and all of a sudden nothing. Unplugged the pc for about 15 mins and it fired back up and ran fine, for awhile- then nothing, no case fans, no lights, nothing.

So, I ordered a 1kw quad rail from Antec. Installed it and fired it up and it ran, but I noticed the 120 mm case fan wasn't turning. Before I could shut it down, it quit on me and would not start back up. I checked the fan and sure enough the bearings had died. I replaced the 120 mm fan with a spare 80 mm fan just long enough to verify the source of the problem and it ran fine. The Tagan psu (as well as the Antec) has an over current and over voltage protection circuit and on the initial load of the failed case fan the psu shut itself down.

I brought my Fluke meter home from work, but I haven't verified that the Tagan psu wasn't damaged yet. I hope to do that in the next day or so.

[HTM~CheeZmonZter]

http://www.frozencpu.com/search.html...&go.x=0&go.y=0


This one isn't that much.......

[Coyote]

I ordered one with a LCD display. I just didn't want to pay $40-$50 just for overnight shipping. I'll get it by the end of the week I think.

[Coyote]

Okay! Let the saga begin. First, up, let's test the PSU:

I got a Rexus PST-3 Digital power supply tester with LCD:
http://www.newegg.com/Product/Produc...82E16899705003

today and plugged it in. At first glance, everything read just fine:

+5V : 5.1V
+12V1 : 12.2V
+3.3V : 3.3V
-12V : 12.0V
+12V2 : 12.2V
5VSB : 5.1V
PG 390ms

Alright... so I then tested each and every one of my cables. Al of the 12V lines (PCI-e) work fine. When I plugged in the SATA and IDE/floppy connectors, I never see the 5V LED light up. However, when I shove my multimeter into the plug directly, I see that there's 5V registering. So I'm kind of suspecting the 5V LED on the tester... it flashes on and off sometimes when I plug in a connector, but it is never on for more than an instant. I read a review on newegg saying that some guy encountered this problem with a different PSU and that it was okay on his machine.

Huh...