PC keeps going in rebooting cycle... help please :)

[Ali N]

In late September I bought and built my own computer and have been over the moon with it since and have had no problem at all with it. It was my first build however, I'm pretty sure that it's all done right.

Here is the spec:
-Intel i5 750
-MSI GD65 Motherboard
-ATI HD4890 1gb xfx
-8gb of Corsair Ram
-750w Corsair HX PSU
-Noctua NH-U12P SE CPU cooler

and all this is housed in a Silverstone Raven RV02

Now here's the problem:

Over the past few days I've had my computer on from about 10am to 12pm. But when I go to boot it up in the morning after. It goes in a cycle of reboots. I turn it on, the fans whir up and the lights come on, then 5 or so seconds later it goes off.

It doesn't even get to the bios screen and it does this from a random number of 3 reboots to around 20 reboots on some mornings. As soon as the computer gets to the bios screen however everything is fine and it boots up normally and there's no problems with it when it's on and working

It's just confused me how it's all of a sudden done this after 3 months of working perfectly.

Btw, I'm running the Windows 7RC but I've got a copy of Home edition that is waiting to be put on at some stage

Hope you guys can help

[PubZombie]

Hi buddy,
had a similar thing happen on my last build and it turned out to be a dead ram stick which was messing around with things on post. does your motherboard have a LED fault code window/screen?