GA-8IPE1000-G Dual Channel RAM Problem

Hello,
Recently I have been upgrading my PC and bought 2 RAM sticks 512 each. And have been working in single channel perfectly later, I bought another 2x512MB of the same model stick exactly such that the 4 are 100% identical, when I boot up using 4 sticks @ 2GB in dual channel my windows gives a BSOD with the 0x0000008E error. However, 3 sticks run in single channel perfectly @ 1.5GB
I have no control whatsoever on the choosing of single/dual channel nor on the specification of the RAM voltages or timings in BIOS, there are no options even related to SDRAM in BIOS and a BIOS update has not changed anything at all, I tried restoring defaults BIOS, but still I got the BSOD same if I loaded BIOS with optimized settings.
Has anyone got an idea what should I do?

Thanks

Edit: Another note is that the 4 sticks are 100% compatible with my mobo

I fixed my problem by setting frequency in BIOS to 166.

Thanks