I do not believe your motherboard will accomodate the Phenom II cpu whatsoever; the link to your motherboard which shows "processor upgrade information" details upgrade of phenom cpu's (first generation phenom's) that is
The chip set and the Bios has to support the CPU, HP is not known for Bios updates to allow newer CPU's on their motherboards.Socket type: AM2+
Motherboard supports the following processor upgrades:
*
Phenom with Quad Core (Agena) technology (AM2+) up to 9600 (up to 95 watt)
*
Athlon 64 X2 with Dual Core technology X2 up to 5600+ (up to 89 watt)
*
Athlon 64 less than 4000+
*
Sempron less than 3800+
No is it a AM2+ socket??? I know now that the am3 chips have 938 contacts and socket am2/am2+ have 940 so it will fit but I don't know maybe I should take the plunge...
From> Motherboard Specifications, M2N68-LA (Narra3) HP Pavilion Elite m9400f Desktop PC - HP Customer Care (United States - English)showhide
Processor upgrade information
Socket type: AM2+
Motherboard supports the following processor upgrades:
*
Phenom with Quad Core (Agena) technology (AM2+) up to 9600 (up to 95 watt)
*
Athlon 64 X2 with Dual Core technology X2 up to 5600+ (up to 89 watt)
*
Athlon 64 less than 4000+
*
Sempron less than 3800+