lol i do advise reading the manual as you will see in it that it does not support 800 lol.
I did, and this is what it says:
Memory 4 DDR II DIMM memory slots (supports up to 8GB memory)
Supports dual channel DDR II 800/667/533 unbuffered DIMMs(Note 1)
Supports 1.8V DDR II DIMMs
It's possible the mobo may have been updated to support DDR II 800 since you got yours. In any case 800 is a bit out of my price bracket.
Anyway, thanks for the replies folks.