This is probably too technical to be appropriate for GQ… I’ve also posted to enthusiast forums without too much result so I figured I’d give it a stab.
Hardware is:
Corsair 520hx psu, antec 900 case, DFI tr2s dark (p35) motherboard, 8800 GTS video, 2x2gb ddr2 ram, core 2 duo.
I had a running, fully functional computer when I accidentally pulled the power cord out from the PSU when I was untangling wires.
I plugged it back in, at which point the fans/lights all powered up (I didn’t hit the power button at this point, it just went on by itself), but there was no POST. I held the power button down to shut it off, then turned it back on - the fans/lights all came on (including the loud graphics card fan at 100%), except the 200mm fan on top which seemed like it was struggling to move (movingly slightly back and forth).
So I turned it off and left it alone for a few minutes, then tried to turn the power on again. All lights/fans came on, including the 200mm fan for about 6 sceonds. Then the whole thing shut down for about 3 seconds, and then came back on again on its own and stayed on until I turned it off.
Since then, when I turn it on it either does the 6 seconds on, 3 seconds off, back on indefintiely thing, or it comes on and stays on the first time
When it does this there’s no post beep or any sort of noise except the fans and I think the hard drives spin up but I’m not positive. The monitors won’t even click out of standby mode.
I cleared the CMOS, tried unplugging parts 1 by 1 until I had the bare minimum with no change. I unconnected and reconnected everything, I put the motherboard outside the case in case there was a short, reseated the CPU, every little thing I could think of. Nothing.
I plugged my PSU into my old computer - the new computer uses a 24 pin ATX power connector and 8 pin 12v, and the old one uses a 20 pin and 4 pin 12v, so I’m not using exactly the same connectors on the PSU, but I booted the old computer off the new PSU successfully, went into the voltage monitors and they were all normal. This suggests the PSU is okay - but there’s a chance it’s failing in a way that powers the old computer but not the new one (that requires extra pins, a PCI-E power connector, etc).
The motherboard seemed the most likely culprit so I replaced it with a GA-EP45-UD3R. It still doesn’t work, but it has some new weird symptoms and now I get beep codes.
First, the CPU fan, in the “CPUFAN” socket, does not power up when the system powers up. It starts either 12 or 25 seconds after boot, depending on the hardware configuration. The GPU fan and PSU fans start right as the power switch is pushed.
And sometimes the system will instantly power off when I hit the power button, and sometimes it will require me to hold it for 5 seconds. What does it mean, that sometimes it’s reaching different stages of booting?
If I run with nothing but PSU and CPU, no video, no ram, no HDs, etc, it powers on, continous short beeps at the same interval for 11 seconds (long enough for 8.5 beeps), then it powers off for 2 seconds. At which point it powers itself back on, runs for 11 seconds (with 8.5 beeps), and powers itself on, then restarts itself, etc.
“Continuous beeping” in the motherboard manual indicates a power failure.
If I plug the video card in (along with the PCI-E power connector) but still nothing else, it powers up, beeps 3 times, powers off, powers itself back up, beeps 3 times, repeat. The motherboard manual does not indicate what three short beeps means. I don’t think it’s the “continuous beeping” above, because it distinctly beeps 3 times, stops, and then powers off.
When I then stick in 1 ram stick in addition to the video card, it powered on for 5 seconds, powdered off, powered on again, and then roughly 15 seconds later gave off 1 long beep, and 2 short beeps (I think, it actually sounded like 1 long beep, and then 1 short beep where the volume dipped in the middle of the short beep, I think it’s meant to be 2 beeps).
The manual says 1 long, 2 short beeps (What it probably is) is a gpu/monitor error. 1 long, 1 short (which it maybe is) is a memory or motherboard error. It then powered off as soon as I hit the power button.
I rebooted with the same hardware configuration and this time it didn’t power off first, it just beeped at 15 seconds in. Even with the same configuration as last attempt, now it took 5 seconds of holding the power button to turn it off, it didn’t do it instantly.
Then I tried removing the video card again and switching the ram to another slot. This time it powered up, 1 long 2 short beeps after about 8 seconds (which makes sense since the video card is missing), the CPU fan came on a few seconds after that at about 12 seconds, and it instnatly powered off when I hit the power button.
I put the video card back on, with the ram the same as above, and now after about 22 seconds it gave 1 long, 2 short beeps. 3 seconds later, at 25 seconds after power on, the CPU fan came on. It instantly powered off when I hit the button.
I then moved the ram to the third slot over, and it powered on - but no beeps this time. After 25 seconds, the CPU fan kicked on.
Whenever I had the video card in, I had it plugged into a monitor - and it never clicked out of standby mode.
I am now completely perplexed. So I came here hoping that someone would give me some idea, any idea, what’s going on, or at least what I can try next.
TO add: On a normal boot back when it worked, my video card would spin up to 100% fan when I hit the power button for about 2-3 seconds until it booted up its own bios and got its fan profile and lowered it to like 40%, so you’d hit the power button and get LOUD…2 seconds… quiet. Now it just stays on full blast, which I assume means the video card isn’t getting to the point where it consults its bios. I’m not sure what that means, but I thought it was worth adding.
I’m working on getting good replacement parts to test it with, but anyone I know locally has different hardware that’s not compatable… I’ve got a friend mailing me an old video card to test that. I can’t afford at the moment to just keep buying new parts and hope I hit the right one. So does anyone have any idea what to do?
Another question I can’t get a straight answer to: Does the presence of beep codes indicate that my CPU is functional? That is - if you had a functional system and removed the CPU and tried to boot, would it beep? Or would it be silent because the CPU is necesary to get to the stage of POSTing where it would beep?