790XTA-UD4: power up only for 2 or 3 seconds?

[eromero]

Hi!
I would appreciate some advice. Sometimes my computer turn on for 2 or 3 seconds and then suddenly turns off. This happens about once every 15 attempts. I have to unplug the PSU or turn off my UPS for a few seconds to get it boot up and function normally. My system is a new GA-790XTA-UD4 motherboard  + new AMD Phenom II X4 955 BE +  2 SATA HD + 2 CD/DVD/RW +  new PSU Thermaltake True Power 550W + Windows 7 32 bit.

[absic]

Hi there,

I'm running the same motherboard with BIOS F4A but with an X6 1090T, 8GB of Corsair Dominator RAM, Corsair 620 Watt PSU, 2 X SATA2 HDD's 2 X SATA3 HDD's 1 X SATA2 DVD/CD Writer, Sapphire 4850X2 Graphic Card Microsoft USB keyboard and mouse and I'm running Windows 7 Ultimate 64Bit.

At the weekend I had to re-install my OS and guess what, I encountered exactly the same problem.  Powered up and the system decided to shutdown after 2-3 seconds and the only way to get it started was by removing the power lead from the wall socket, waiting 30 seconds or so and the plugging it in again. The PC then fired up OK. It did this a couple of times and has since settled back down. I even mentioned this to DM as it was so sudden and unexpected and also I had not had this happen on this system before.

I haven't got to the bottom of it yet and am still completely in the dark as to why this has happened. At first I thought that I had not connected something up properly and went through all of the things I would normally do but haven't found any logical reason. It even did it once when I had attached a spare Power Button that I have for testing purposes as I thought the Power Switch on my Chassis might be faulty.

As I said earlier, my PC has now settled down and is once again booting as I would expect but apart from it being a temporary glitch, I'm afraid I haven't been able to pin down the problem. and am still trying to find the cause.

[absic]

OK,

Today had to go inside my chassis to reconfigure a few things and guess what, the same thing happened again! 

Now, I'm nothing if not persistent when it comes to this kind of thing and annoying niggles of this nature really tick me off so, after a bit of playing around I discovered the culprit. It's my Graphics Card!

I have a rather large Sapphire 4850X2 sitting on my motherboard and, when I adjusted some power leads there was enough movement to unsettle the card in the PCI-E slot. Gravity and these larger cards don't seem to go together very well. I reseated the Card and everything is back as it should be.

I played around for some time and I was able to replicate the fault and with  a slight movement of the GPU the PC would Start to BOOT and then shutdown within 2-3 seconds. So check that your Graphics Card is firmly in place (I thought mine was) and check that you are not getting a lot of case vibration as this might be the reason for your fault too.