Blank monitor on power up

[shankenstein]

I built my pc in December 2009. It's been great. I was playing Starcraft II and the computer froze and was not responding for about ten minutes. I manually shut the computer down by holding in the power button.

Now when I turn on the computer everything powers up in the case, but there is nothing on the screen. The monitor just stays in sleep mode. I've tested the monitor with a different computer, it's working fine.

I confirmed that the hard drive with the OS installed is spinning. I do notice that all the fans in the case seem to be running on full blast when I turn it on. It did not do this before the problem. I have not been able to confirm that the second hard drive is spinning, although I'm not sure if it typically does during start up.

I'm desperate for help. I'm really frustrated and bummed about this. This is my first home build and I love it.

I need some direction in how to isolate the problem. Thanks in advance for your help!

Windows 7 Professional
Asus P6T motherboard
Intel Core i7
Thermalright Ultra-120 Extreme CPU Cooler
CORSAIR DOMINATOR GT 6GB (3 x 2GB) DDR3
Corsair-1000W ATX CPU Power Supply
Dual GeForce 9800 GTX+ 512MB DDR3 256-bit in 2-way SLI
Western Digital-VelociRaptor 300GB SATA Hard Drive (OS installed)
Western Digital-Caviar GP 1TB SATA Hard Drive
Plextor DVD Burner
Plextor Bluray Burner
LIAN LI PC-B25B Black Aluminum ATX Mid Tower
APC-1300VA Battery Back-Up System

 

[geekapproved]

Have you tried pulling the cmos battery for a few minutes?

 

[shankenstein]

Have you tried pulling the cmos battery for a few minutes?

You mean on the motherboard right?

 

[guavasauce]

since the fans are running at full blast, but youre not booting, that means your getting stuck in POST.

best place to start is cycle booting with single sticks installed to rule them out. if none of them work, they may be good, and the problem may be your mobo or cpu.

 

[geekapproved]

You mean on the motherboard right?

Yeah could be stuck in sleep mode. Had it happen to me before and thought I had a defective video card and rma'd it only to find the card was fine.

 

[shankenstein]

Yeah could be stuck in sleep mode. Had it happen to me before and thought I had a defective video card and rma'd it only to find the card was fine.

Ok I'm going to try this before removing video cards. I'm assuming I should expect to have to reset all the bios settings after this, is that right?

 

[geekapproved]

If you have changed your bios settings, yes you will likely have to reset them.

 

[shankenstein]

I am thinking it's your PSU although you do have a beefy one... next would be a bad video card... take one out and see if it works swap in the other video card... then you should swap in a know working PSU.

I tried removing the cmos battery. That did not help. I removed the first video card and it seemed to fix the problem. The computer started up and after resetting the bios I was able to start up normally. I tried moving the working video card to different pci slots on the motherboard and it worked fine. The other video card did not work in any slots. I assumed it was bad. I now have one working video card installed.

However, after several updates and restarts, the issue came back. Now when I turn on the computer, I get one continuous beep followed by three short beeps, which means there is no VGA detected.

Where to go from here? Is this a now a motherboard issue?

 

[shankenstein]

I switched the working video card to the 1st pci slot from the 2nd slot. It seems to be working again.

I want to get a new vga card to replace the busted one but now I'm not confident that the motherboard isn't the issue. any recommendations?

 

[geekapproved]

If any of the video cards work in slot 1 and slot 2, then it's not the mobo.

Those video cards are quite old, so it may be time to replace them with a single faster card thats less power hungry.

What does your motherboard manual say about the beep sequence?

 

[shankenstein]

If any of the video cards work in slot 1 and slot 2, then it's not the mobo.

Those video cards are quite old, so it may be time to replace them with a single faster card thats less power hungry.

What does your motherboard manual say about the beep sequence?

that meant it didn't detect vga.

It recommended slot 1 for a single card so i moved it to that slot and it seems ok.