Gainward Radeon 4850 Monitor flickers when stressed/gaming

[penetralia13]

I installed on my mums pc an HD 4850 to be able to play Bad Company 2 but ever since i m going crazy.No matter what game i run monitor flickers like i have 100 mobile phones next to it and looses signal, when i shut the game everything goes back to normal.There is no overclock and the temperature is just fine @47 Celsius since i installed an aftermarket cooler on it (http://www.scythe-usa.com/product/vga/002/scvms1000_detail.html)
I tried almost everything re-sited the card on mb, clean installed new drivers, even reinstalled the aftermarket cooler but same thing...i m loosing my mind here!please help.
Here is how the problem looks like.
http://www.youtube.com/watch?v=qQaLHOnrmMk
Thanks for reading

 

[hunuok]

What PSU are you using?

A 4850 + components should require ~400W.

 

[penetralia13]

thats something i should had mentioned at topic start sorry.its a 500watt power supply,an 9800 gx2 runs fine PSU is ok.

 

[hunuok]

Your PSU seems fine.

Have you tried the card on another rig?

Is your MB compatible with AMD cards?

Try RMAing the card if problems persist.

As a hail mary, try using Cat 10.3 or 10.4 drivers.

IMO, anything after 10.4 is utter fail.

 

[wa1]

It seems like a defective/bad card...
Try your card in different PC, if the same problem exist then your card is going bad...

 

[penetralia13]

I did try the card on another pc and it works just fine!i also tried catalysti 10.3 to 10.7 and result is the same.I m on an Asus P5K-VM.I ll try updating the mb bios hoping it will fix the problem

 

[penetralia13]

Tried bios mb bios update but still same thing...

 

[hunuok]

I would RMA the card.