I forgot to write that (this is the error on my second test on 285*9):
FATAL ERROR: Rounding was 0.499999591 expected less than 0.4
Hardware failure detected consult stress.txt file

If you want I could picture my BIOS if that would be good.

Please help.
Sorry for my English.

Tnx

I have:

DFI LanParty UT nf4 Ultra D
2*512 TwinMos Speed Premium PC3500 / DDR433 Dual-Channel Kits
AMD Athlon 64 3.0 Venice
PNY GF 7800 GT
Hitachi T7K250 160GB 7200
Tagan TG420 U01