Screen flashing when OC Sabertooth 990fx

[SirFoxx]

Hello there--

Before I got the sabertooth R2.0 board and fx-8350, I used to own an AMD 5000+ BE (still have it!) and I would OC by upping the voltage and the multiplier, and it was stable for me on a crappy nettle2 HP board at 3.0ghz. So, when I upgraded, I got this board and CPU to ensure that I could up the voltage and CPU with no problem.

I don't like poking around in the efi Bios, so I got AMD's overdrive program and I OC from there. I have read all over online that people have gotten this CPU around 4.8ghz and have it stable. Mine is also "stable" I think when I bump the two settings up. But, when I hit anything past 4.7, my screen will flash black a few times, and windows aero will change the setting to windows classic for no reason. Also, when the screen flashes black, some of the toolbar icons will turn black and stay that way till reboot. My temps are within very safe temperatures, so temp isn't a problem. Why do you think my screen is flashing like this?

Specs are as follows:
Asus Sabertooth 990fx R2.0
Apevia 700w PSU ATX-AQ700W-BK
G.Skill Sniper 8gb 1866mhz
AMD fx-8350
CM v6gt Cooler
BFG 9800gtx

Sorry I don't have model numbers for some of my parts. I am posting from my laptop at the moment.

 

[ihog]

It means the overclock isn't stable. If you're OCing, you always want to test with something like Prime95 or Intel Burn Test each time you bump the multiplier. I would venture to say that it was unstable way before you got to 4.8 GHz.

 

[SirFoxx]

What tests, and for how long, should I run with Prime95?

 

[ihog]

SmallFFT, for about thirty minutes. I recommend using Intel Burn Test because it's simpler.