Computer stopped booting

[Bravo]

I've been experiencing random reboots and odd power up problems over the last few months with my semi new computer, yesterday after 3 failed start up where my computer would freeze at the motherboard splash screen I finally got it to boot into windows but could not get any network activity and could not refresh my IP.

I had assumed it was the motherboard (Asus P5K-SE) because of the freezing before it even tried to start the OS. So I went out, bought a new motherboard (Asus P5Q)

Took out the old motherboard, hooked up the new one, got everything installed and tried to start it up... power goes to the board for a split second and then doesn't power on. I checked all of the connections, and called asus support. After a long trial and error session I was able to come to the conclusion that the motherboard was not starting when my 8800 GT 512MB was plugged into the board, with out the card, and with a 8600 GT it worked fine.

When I took out the new board and went back to the old one I had the exact same problem with it not booting with an 8800 GT, which was incredibly odd seeing how I was able to run this card in this machine for last few months.

I assume the problem is the power supply, but have no way of knowing for sure. The video card requires combined 24A on the +12V. I'm using a OCZ GameXStream 700W Power Supply, which is made for SLI, so I had assumed it could run 1 8800 GT with no problems at all, but on the side it has

+3.3V(36A), +5V(30A), +12V1(18A), +12V2(18A), +12V3(18A), +12V4(18A)

I'm a little unclear on the combined part, I've read else where it has to to with the 12V Rail.

Any thoughts or suggestions?

[The_Whack]

WARNING*** I'm no IT Expert**WARNING

Ok, now thats outta the way......

I have an Asus PK5-E MB and had the same problems your describing, in fact sometimes it would not even POST.

MY problem was the Ram, the voltage in the default BIOS was set too low. I went through hours of random reboots or no POST at all... also fried 2 sticks in the process. What I did was go to my local computer big box store and buy a stick of cheap ram, installed it, booted to BIOS and set the correct voltage. Shut down, popped in my better RAM and everything worked perfectly. Returned the cheap RAM.

Hope this helps.... Good Luck!

[Sarduci]

24A? As in 24 amp? Holy crud! I don't have a big enough electrical hookup for that anywhere in my place! Max load on a 20 amp circuit is 80%, which is 16amp. You'd need 30 amp for just your video card!

Try a new power supply. If you have electrical skills, you may want to run a meter against your outputs, but if you needed me to tell you that DO NOT attempt it.

But then again, your video card my have just died because it was defective, hard to say.

Edit: My system, 880GTS, quad core, 4 disk drives runs off of a 400w PS with no issues. In fact, under heavy load, it barely crests 220watts at the wall.

[Bovidae]

24A@12V is roughly equivalent to 2.6A@110V
A*V=W

There are many reasons your system is doing this. If it is stable enough to check the bios settings of the RAM, Bus, processor, etc; then do that. I always suspect the PSU first. I don't know why....

I have always relied on the replace with known good, theory. I take the suspect video card, put it into a working computer. Does it work? check. Take the PSU from the working computer, use it to power the broken computer. Did that fix the problem? and so on....

[Bravo]

What should these settings for the ram be? Any link to a helpful page? I have 4x 1GB DDR2 667 ram, I think. Very small chance it could be 800

[Sarduci]

24A@12V is roughly equivalent to 2.6A@110V
A*V=W

OK, I'm glad I'm not going crazy. I knew I the numbers I was scribbling down were off somehow. Too many shocks from trying to fix a bad wiring job this weekend. Never try to fix electrical wires by sticking your arm into a hole and hoping for the best. Especially if you didn't wire it in the first place.

[Sarduci]

What should these settings for the ram be? Any link to a helpful page? I have 4x 1GB DDR2 667 ram, I think. Very small chance it could be 800

Try bumping up the voltage. It's set to 1.xx right now, just add .01 to it, reboot, and see what happens. Don't go anymore than +.05 TOTAL if you're not sure what you are doing. This will fix a low voltage condition if your RAM is running with bad power.

[The_Whack]

What should these settings for the ram be? Any link to a helpful page? I have 4x 1GB DDR2 667 ram, I think. Very small chance it could be 800

Safe thing to do would be to go to the RAM manufacture site and get the proper settings.

EDIT or go to a retail site like ncix.com or newegg.com and see if they sell the same ram, usually post the specs.

[Wilbur]

Find your RAM specifications. Look it up on the manufacturers website.

If you have a multimeter put it across each of the pairs to see if you are getting the correct voltage across them.

[Ughmahedhurtz]

What should these settings for the ram be? Any link to a helpful page? I have 4x 1GB DDR2 667 ram, I think. Very small chance it could be 800

Check the manufacturer's website for "product data sheet" or specifications or something like that. It should have all that listed if it's a major brand.