You've got the same motherboard as me, I also recently upgraded to SSE3 :-D

I bought an 4200 X2 939 off ebay. It works pretty well if you boot with IDLEHALT=0 to avoid the random glitches caused by the dual core. My system xbenches at around 120 with this processor.

I use a Athlon 64 X2 4200+ on a 939 Socket as well, and it works fine. :-)

Thnx ppl,
I go a processor fishing...
Btw X2 - both cores work?

Yes, both cores are working fine :-)

http://saved.im/mtk3mjzzm245/bild2.png