Jittery sound/screen on bootup - diagnostics help?

[Guest]

So a friend's PC was knocked onto its side the other day. The internals appear to not have suffered any damage as far as we can tell, aside from one worrying little thing. On startup, the first screen and sound flicker and cut in and out until the sound finishes, but after that the computer works as normal.
Here's what it looks like.

Files are all safe, temps are fine, GPU and CPU perform fine under load. If anyone has any ideas what could be the cause of this, it would be appreciated.

In case it matters, specs:
AMD FX-6300
Zalman CNPS10X OPTIMA
ASRock 970 Pro3 R2.0
8GB Mushkin silverline DDR3-1600
Kingston SSDNow V300 120GB
Hitachi deskstar 1TB 7200RPM 3.5"
Gigabyte R9 270X windforce
Enermax ECA3253-BW
EVGA supernova NEX 750W 80+ gold

 

[smorizio]

reseat the ram and the gpu. check that the cpu is still fully seated. clear the cmos out and reset the settings to see if the mb glitched out. if it not hardware it may be a damaged driver or program the loading at startup. use msconfig turn everything off see if the sound and video is fine.

 

[theunliked]

Do you get normal sound after that?