F3-12800CL8D-4GBECO and EVGA P55 LE

[shoreweb]

Been running 4gb (2 sticks) of F3-12800CL8D-4GBECO without a problem, all bios settings on auto except "lo gap set to 3gb" per suggestion from evga support.
Both the Bios and windows shows 4 gb of mem in dual channel.
When I try to add two additional sticks of the same memory, filling all four slots for 8gb, my system does not boot.
I'm using an i5 750 and win 7 64bit.
Does anyone have a suggestion?
Thanks

[shoreweb]

Could someone help me manually set correct ram setting in the bios.
Everest and Bios say timings set at 9-9-9-24, also both say speed set at 1333 (not 1600).
I've set voltage to 1.35v from the auto setting of 1.50v.
Just wondering how the setting in bios should look...thanks

[GSKILL TECH]

Simply set timings in BIOS to 8-8-8-24-2N. DDR3 Frequency 1600.

To operate 4 sticks, you will need to raise CPU VTT Voltage to 1.25V.

Thank you
GSKILL TECH