GA-MA790X-DS4 heat isuess?

Hi there guys, english is my 3:rd language so spelling might be poor...

10 days ago i purchased the following:
Gigabyte GA-MA790X-DS4
AMD Phenomx4 9550 BE
Corsair 2x2 Gig 800Mhz

I installed Vista x64 without problems and downded Prime95 to test stability.
Well, the cores crasched one by one. Thought the CPU was the reason but taking the stepping down to 12x didn´t help, nor 11x. At 10x the system stabilized.
Tested the memory in memtest for 6h, no problems there...
Tested the CPU with Prime95 again but this time in "small FFT s" (only CPU test) and no core crasches occurd.
It´s the mainboard guys, must be...
I returned the lot to the dealer for testing, we´ll see what they say...

The reason I´m writing here is that i read that this board really cant cope the Phenom series (dispite what GB claims), at least not without adding extra heatsinks on it, is this true? Also the SB600 And Phenom I read doesn´t go so good together?
Should I change it for another one, say the Gigabyte GA-MA790X-UD4LK?

Thankful for any comment that can point me to the right direction.

Pretty much, all modern computers are limited by their thermal solution - that's why there's a booming business in heatsink/fan combos; it's not the MOBO's problem, it's your design problem... Mine was designed specifically to move a lot of heat, from the chips, ouside the case, and loafs at 4+G - unfortunately, it was designed for a big, cool, open basement, and is now making an intolerable space heater in my small room - hence - the radiator/pump combo going into the basement...