q9450 4870x2 4gb(2x1)mushkin 996602 at 1800 8-8-7-20 1.9-1.95V i've flashed to the latest bios F6a wich is a beta version with @bios

tested the FSB 450 for 3 hours(couldn't wait for 8h) with prime95 with no errors..i've lowered the memroy strap so it will run under stock vlaue so i know that isn't the problem here.With memtest, at 1800Mhz it passed a few times with no errors then it froze...i can normaly boot but always get vista to freez when it loads at these setting.i've reinstalled vista32 premium so the OS isn't a problem...at 1600 it worked fine until i got the 4870x2 then games freequently crashed and had graphical errors along with that wich happend when i pushed FSB over 333 default...can you help me out??

Robust Graphics Booster___________ [Auto]
CPU Clock Ratio ____________ 6
Fine Clock Ratio ____________disable
CPU Host Clock Control_ [Enabled]
CPU Host Frequency (MHz)__________ [450]
PCI Express Frequency (Mhz)_______ [100]
C.I.A. 2__________________________ [Disabled]
System Memory Multiplier (SPD)____ I USE THE B STRAP AND THE D STRAP MAINLY
DRAM Timing Selectable_______ SPD __ [Manual]

Performance Enhance = [Standard]

CAS Latency Time________________ 8
Dram RAS# to CAS# Delay_________ 8
Dram RAS# Precharge Delay_______7
Precharge Delay (tRAS)__________ 20

ACT to ACT Delay (tRRD)_________ auto
Rank Write to READ Delay________ auto
Write to Precharge Delay_________ auto
Refresh to ACT Delay______________ 9
Read to Precharge Delay__________ auto
Static tRead Value_______________auto
Static tRead Phase Adjust________ 2T(1T WON'T BOOT)
CPU/PCIEX Clock Driving Control [800mV]
CPU Clock Skew Control [normal]
GMCH Clock Skew Control [Normal]

System Voltage Control____ [Manual]
DDR3 OverVoltage Control__ +0.40-0.45
PCI-E OverVoltage Control_ [Default
FSB OverVoltage Control___ +0.2
(G)MCH OverVoltage Control +0.25
CPU Voltage Control_______ 1.3 from 1.25 standard...any help here plz