According to HP, the motherboard supports the following processor upgrades:
- AMD Athlon X2 (Bt)AMD Athlon 64 X2 up to 6000+ (W)
- AMD Phenom Triple-Core up to 8xxx (AM2+) (Toliman)
- AMD Phenom Quad-Core 9xxx series (AM2+) up to 9850 (Agena)
The Phenom 9850 BLACK EDITION (part number HD985ZXAGHBOX) should be the fastest supported CPU.