Intermittent disk boot failure on new build + some other problems

[lykmeraid]

Hi everyone.

I recently bought some computer parts and was hoping for some smooth sailing. Alas, some problems have risen up

The system:

AMD Phenom II 955
Gigabyte 790fxt-ud5p motherboard
4 gigs of OCZ RAM
5770 Vapor-X
Corsair 750W PSU
Samsung Spinpoint F3, 1 TB

The problems:

Well, the main issue at hand is that I get a DISK BOOT FAILURE error about 50% of the times I try to boot up. When I reboot again, Windows boots up fine (if I'm lucky enough to get past the disk boot failure this time at least). I find it strange that there's no consistency as to when the error occurs, seems completely random.

I work a lot and I only have a few hours per day to troubleshoot, so I'm hoping to get some guidance here to isolate the problem as fast as possible. The plan is to run a hard drive diagnostics test when I get home this evening to scan the drive for bad sectors. If that turns out fine, I will try a different SATA cable. Is this the sensible thing to do, or do you think the problem lies elsewhere ?

I'm also thinking it might be a motherboard problem, because of some other issues I've discovered. I've connected my TV to the computer via HDMI. During the bootup process, the image is displayed on my TV (which I thought was strange, I always thought windows needed to be booted before you could see the image through HDMI). But then, when Windows is starting, the image is gone, and even though I've tinkered with the display settings I can't seem to show my desktop on the TV screen.
Furthermore, I can't seem to get any sound to my headset (it always says no output device is plugged in, I've tried both the front and back audio jacks).

Any help concerning the issues is greatly appreciated

 

[lykmeraid]

Guess I should add:

I've installed the latest audio + video drivers. I tried installing the latest BIOS update but the .exe file won't open from windows 7.

 

[Paperdoc]

Some motherboards have a setting that allows you to delay the start of hard drives for a few seconds, just to ensure the PSU output has come up to full specs before loading it. Does yous have that feature? Maybe delaying the HDD startup would solve its apparently random problems. the clue here I'm looking at is that it always fails when first turned on, but sometimes is OK when rebooted immediately.

On the matter of the BIOS update, read the manual or notes on that system carefully. Some BIOS update tools are designed to run under DOS only, and will NOT run under Windows. And some .exe files are actually self-extracting .zip files that will simply generate a set of actual data files used for BIOS updating - that is, they do not DO the updating, they merely create the files to be used later by the real updating utility.