GPU Stops Running After A Second

[ninjaf1sh]

Hi guys,

I'm in a bit of a pickle at the moment. My PC was running fine yesterday but today showed a cable not connected error on my monitor. I checked for loose connections or a pinched cable but everything was fine. On further inspection I realised that when I start up my PC, all the fans run, the lights come up, the HDD spins but the GPU fan stops after a second. my motherboard doesn't have a VGA port so I can't use my PC at all. All of the other components seem to be working except the GPU.

I checked out the forums for a similar situation and found one where the PC shut itself down due to over heating but the fans etc. kept running due to improper earthing. Considering that to be the problem I opened up my processor/heatsink and sure enough it had dried up and flaked and there seemed to be burnt thermal grease at the edges. I bought new thermal grease and applied it but I'm still getting the problem.

I've tried diagnosing it in a limited way because my mobo doesn't have an onboard led and a speaker(so beeps are out of the question too)
Here are a few things that I DID notice and am hoping will help you guys figure out the problem.

1)Keyboard LEDs
When my graphics card is connected all 3 LEDs on my keyboard light up for a second before going off. This happens when my PC usually boots. However on booting one light stays on..here they all go off after a second, is the PC shutting itself down?
When I disconnect my GPU only one light comes on and stays on.

2)All components SEEM to be running
As far as I can tell all the other components seem to be working. Keyboard lights up, speakers come on, mouse laser lights up, cabinet on/battery led lights up, DVD drive led lights up, HDD spinning

3)PSU problem(?)
The PSU which I had first bought gave me a similar problem where it was defective and gave a very low supply of power where the fans came on but the GPU didn't. The company replaced the PSU and the new one was working fine(although the casing looks a bit off). The difference between then and now is that the old PSU fan didn't work and it was obvious power supply was low due to the reduced speeds of the fans. Here the fans seem to be running quite fast and as mentioned earlier all other components seem to have power.


Edit: I did notice something odd yesterday when my back USB ports didn't seem to be getting full power. My external HDD wouldn't detect and HDD LED was quite dim as compared to normal. However it worked fine when connected to the front ports.


4)Funny Sounds
A funny scratching/screaking(yeah a made up word) starts up for a second when I turn the PC on. It seems to be coming from the processor area and the stop in the sound coincides with the stop in the GPU fan. It may be the CPU fan. It goes like skreeeeeeeee-everything running-no funny sound-GPU fan stops.
This sound MIGHT have been there earlier when the PC was running. You have to listen closely to here it.
There also seem to be some 'ticks' (tickticktick) after a couple of seconds. I've heard these before in my old PC but I dunno what they are about.

This is all I have at the moment. I don't have an alternate PC to test stuff on, I can't check bios/CMOS, I have no beep test.
I'm reluctant to take my PC to the computer store as there are just two next to my place and I don't trust them both. I've seen them absolutely ruin my friends computers and charge exorbitant amounts of money, often while giving false diagnosis.
It will be much better if I can figure out the problem as I have warranty on all the individual parts.

I have slaved over building this computer, literally starving myself on occasion to buy it. Its been running with absolutely no problems till now(about 2 months) I'm really shitting bricks here as I don't have the money to do another big repair job.

Please help me out.

The Build.

AMD FX 4300+
Sapphire AMD/ATI Radeon 6770 1GB DDR5
Corsair 450 Watt PSU
WD Caviar Blue 500GB

 

[Tuxedo3]

Hm. I'm not entirely sure, but it seems like either your graphics card is defective or it is not drawing enough power from the PSU. You said all lights and such are working? It just sounds to me like something with the PSU not producing enough power, but I could be wrong. I'll help as much as I can because I know what it's like to slave over a build.

 

[ninjaf1sh]

Yeah all the LEDs seem to be running, so do the speakers connected to USB, mouse, keyboard, external HDD LEDs too. However sometimes the Cabinet battery light doesn't come on. Can this imply low power supply?

Another question I have(sorry if its a little stupid) is can my PC boot without the graphics card? I mean I know I won't be able to see stuff on the monitor but i can still check if the boot is taking place by other peripherals like the keyboard and speakers.
I took out the GPU and the computer doesn't boot. No windows sound, no NumLock LED when pressed etc. So if the answer is yes, the PC can boot without the graphics card then my PC isn't booting.

Thanks for taking the time to help. I don't really have a lot of options where I am. The PC stores here are notorious for their malpractice and I've bought all my parts online(which seems to piss them off to no end)

 

[Tuxedo3]

Wow really? It won't boot without the GPU? That is so strange. It should definitely boot even if there is no GPU installed. Unless there is some setting on the mobo that stops it from booting if there is no GPU installed, I can't imagine that's true though. If you get LEDs and most of the time and sometimes you don't, I want to say the PSU is failing. I could be wrong but I'm not sure what else the problem could be.

 

[ninjaf1sh]

It definitely doesn't boot up without the GPU. Another thing I noticed is that the back USB ports don't seem to be getting power. When I connect my external HDD at the back the LED flickers intermittently although it seems to be working fine at the front ports. This could also give a clue that its a PSU problem?

I read somewhere that PSUs have two rails and sometimes one of them could be malfunctioning. Could this be the case here? Where one rail isn't giving power to the GPU and the back USB but everything else is working on the other rail?