Overclocking issues i7920

Hi guys,
I'm trying to OC my 920 by following NickN's instruction from the 'System to Run FSX' thread in the Hardware section. I thought I'd followed them correctly but when booting up the computer it's only reading 4GB of Ram instead of 6Gb although I get 4.0ghz OC just the 4Gig of ram. Can anybody tell me where I'm going wrong. my specs are-
I7920,
Asus p6tDeluxe V2.
Corsair XMS3 6GB (3x2GB) DDR3 PC3-12800C7 (1600MHz) Tri-Channel (TR3X6G1600C7)
BFG GTX285 OCX
Corsair 750Watt PSU
Any help will be much apprecitaed
I'm trying to OC my 920 by following NickN's instruction from the 'System to Run FSX' thread in the Hardware section. I thought I'd followed them correctly but when booting up the computer it's only reading 4GB of Ram instead of 6Gb although I get 4.0ghz OC just the 4Gig of ram. Can anybody tell me where I'm going wrong. my specs are-
I7920,
Asus p6tDeluxe V2.
Corsair XMS3 6GB (3x2GB) DDR3 PC3-12800C7 (1600MHz) Tri-Channel (TR3X6G1600C7)
BFG GTX285 OCX
Corsair 750Watt PSU
Any help will be much apprecitaed