Intermittent no POST problem.

I've had my carputer in the car for a good two months now and have one problem that seems to pop up occasionally.

The computer will not post at all, and refuses to show anything on the screen at all.

The setup consists of a DSATX power supply connected with 8awg to the battery, and an ASUS E35M1-I mobo with 8 gigs of ram.

The setup will boot up no problem a good 90% of the time, and will randomly do nothing the other 10% of the time.
The light on the mobo will turn green, hard drive will spin, and the monitor will flash "no input detected" before turning off.

Any ideas what could be causing this? I'm going crazy trying to troubleshoot it since it's such a sporadic and random occurrence.

I'm not sure if me using hibernation could be causing this? Could it? I'd assume not seeing as it doesn't even get to the POST process.

Could it be the DSATX which is causing this? It is from nearly 5 years ago, and I have heard some of them have problems with the firmware or something.

Anyone have any ideas of where to start troubleshooting? I just replaced the mobo battery today hoping that may have been causing it. Tomorrow I'll try and update the BIOS to the latest available version.

Any thing else to look into? This is driving me insane!

Updating the bios is probably a good idea. As what your describing could be a chipset comand problem thats not activating the onboard graphics. It usualy corrects itself when you disconnect and reconnect the power source but will still play up from time to time as whats happening in your case.