I bought Antec's P150 case (all hail!), knowing full well the NeoHE430 power supply might not work. The system never started with the NeoHE. All fans spinning, power to the DVD and HD, but no video. I changed back to my bad OKIA 420 PSU from my old case and the system seemed to run fine - for a day. I was playing a game when it restarted on me, and the next time it shut down for good. Same symptoms as with the other power supply - all fans spinning, no video, no beeps.
I bought a PSU power tester from Antec. Both PSU's checked out fine.
I assume either my processor or M/B is dead. I did take out my processor before the case arrived to clean the overflowing silver compound. I made a mess trying to clean it up and per internet lore I swabbed it up using rubbing alcohol and cue tips. Replaced it with standard thermal grease.
Possible reasons my system is dead:
Silver compound shorted my M/B (likelihood? anyone?)
Silver compound shorted my CPU
Static killed my CPU when I took it out, walked across the living room and showed it to my parents. (And handed it to my mom - please hold it by the corners, thanks.)
Graphics are dead (very doubtful - I tried with another card as well)
My PSU tester is lying to me, and both PSU's are faulty
And - if either my CPU or M/B is dead, which is looking very likely, how come a crappy power supply revitalized my system for a day, and then it burned out. One last blaze of glory?
have you tried removing all cards and hdds/cd floppy etc leavin just memory vga and cpu?
try just like that and see if u get ny beeps
then try cpu vga and no ram see if u get any beeps that way.
you said the pc restarted and didnt boot up again, could be somethin is shortin the mb so it is switchin off to protect itself try removing the board maybe some silver compound found its way underneaththe board and is causing a short,
My M/B is outside the case already, no peripherals attached. It looks clean. I've started it with and without RAM, but no beeps. I've read that w/o RAM no beeps indicates that the motherboard and processor aren't communicating - so I can assume one of them is faulty.
I'm guessing if the CPU were dead, the computer would never have started up at all, so I'm leaning toward replacing my motherboard.
If any other components are faulty, they might be tripping the PSU - leaving the PSU unplugged for a few hours normally resets them.
It might be worth building up from scratch - board + CPU (no memory), reset CMOS and see if it powers and beeps for "no memory".
Then reset CMOS again, add memory, wait for beep for "no video". If you get that, reset cmos, add video card - try powering on. I had a similar thing with my Antec 380W PSU dropping out and temporarily killing the board (northwood 2.6C on an MSI 875P Neo). It would boot after leaving the PSU to reset itself, and doing a CMOS reset, but would die again randomly under load (similar to yours).
I replaced the PSU with an Akasa PaxPower 460W, reset CMOS (again) rebuilt the machine card by card starting with video card and eventually found in conjunction with the dead PSU that my TV card now causes the board to trip out in slot 2. Moved it to slot 3 and all is well!
Strange set of events, but its fine now. Only mention it because it sounds similar to your scenario.
Thanks Matt -- that's quite a process you had to go through. You've got more patience than I. I've got a new Gigabyte board from Newegg on the way and will rebuild sometime next week.
I think I'm done messing around with my system on this motherboard. Last time I tried to power up the system, I only had memory and video card attached, with the motherboard sitting on a couple DVD boxes outside of the case. I'd down this many times before; just hoping for a miracle. Anyway, I powered up and the thing let out a squeel of pain - I think from my 6800GT. The sound hurt my ears and I powered down right away. My guess is that fan was spinning way too fast, like the voltages were all wrong, but I don't really know. If I haven't killed my GPU already, I don't want to risk it again by starting it up with this board. I'll just sit back on my heals until my new board comes and dust off these components from time to time.
My bet is that there was a misplaced mounting post that was somewhere underneath the board and grounding it. ...If you have 6 post, but the motherboard is scewed to only 5... then there is a problem ...