Blank screen, CPU/Mobo Problem?

[Orphius]

First off here are my system specs,
Intel p4 3.4ghz HT
Asus P5WD2 Premium Mobo
ATI X800XL 512mb vid card
1gb ddr2 800 Mushkin Ram
430w Antec Power Supply

Alright, so the basis off this problem is my monitor is no longer giving me any picture from my computer. This happend after I was just surfing the web and the monitor just clicked off. I have tested the videocard and ram both in another computer and they work. I sent in the mobo to Asus and they told me nothing was wrong with it and sent it back. Then I ordered a new p4 3.2 HT processor from Newegg and that didn't fix the problem either. Next, I bought a new power supply which was the same brand/wattage that ran in the computer for the past year. I also hooked up another monitor to my computer and still no picture. I also reset CMOS and that didn't change anything. Further looking at the problems, when booting up sometimes it boots up for ~5 seconds then just shuts off which seems to depend on if the processor cable is plugged in or not. Also, USB devices don't boot up. I know its a hardware issue but I have no idea what else I can try, any suggestions? (All of the testing was done with the barebone connected as well).

[fren]

In barebone setup, did you test it out of the case?

Did you power it up through power switch pin terminals from the motherboard? Try to power it up with power switch cable disconnected and momentarily short them with a tip of a small insulated screwdriver. Check what will happen.

See to it there is no faulty wiring connection (wrong power switch connection, etc.) and short between the motherboard and the case. Refer to your motherboard manual.

[Orphius]

Alright, I used a screwdriver to boot it up as you said and I get the exact same problem. The only possibly difference being is that it seems to run for less time (~5 seconds) before turning itself off vs. using the case power switch which is ~7-8 seconds. In addition, if I remove the Intel processor cable when I boot it up, it doesn't automatically restart, it simply boots up and sits there with no picture and no power to usb devices (mouse/keyboard) Any other ideas? ; )

[fren]

According to what you have just described, it looks like your motherboard is the culprit. Since almost all the major components have been changed and tested for its efficacy.

Have you tried to run again your system with the old processor?

See to it that the 6 pin PCIe power cable provided for the video card is attached.

Is your new processor bundled with own fan in a box? Try its own fan. Maybe the rotational speed of your new one is different from your old fan.

Try to insert your memory stick in different dimm slots.

[Orphius]

I have tried the ram in different dimm slots, I have put in the old processor and I get the exact same problem, I have used the new and old fans that were bundled with the retail versions of the processor, and I have even booted up without a fan attached. All of which result in the same conclusion. And that PCI-E cable has been attached to the video card both with the old/new processor. In relation to my ram chip I have tested it in all four of my slots and the motherboard makes no beeping noise nor gives any indication of a problem. Maybe I should call Asus and yell at them for not fixing my mobo when I sent it in? ; )

What you have describe, it's like your motherboard that's causing the problem. Almost all of the major components have been changed.

Have you tried to run again your system with the old processor?

See to it that the 6 pin PCIe power cable provided for the video card is attached.

Is your new processor bundled with own fan in a box? Try its own fan. Maybe its rotational speed is different with your old fan.

Try to insert your memory stick in different dimm slots.

[fren]

You have already tried and changed everything aside from your motherboard. I am certain your motherboard is not functioning well. Call ASUS and send your motherboard back again for further evaluation.

P.S. One more thing, try to boot your system without usb devices attached (mouse/keyboard).

[ramjo]

What about the Processor temprature can u check or confirm whether there is any overheat on that causes it shut down abnormally