Overclocked P5W-DH with mixed RAM

[SquidCombo]

Hi Guys,I've been using my overclocked C2D on my P5W-DH using dual channel 2GB PC2-6400. I have 2GB PC2-5300 lying around so I decided to install it on my system. So far the system is working fine but in the BIOS I still have it configured as DDR-790 to support the overclock which is still okay for the PC2-6400 but won't be good for PC2-5300. Anybody knows what the BIOS is doing for my PC2-5300? Would it automatically set 1:1 for the PC2-6400 and other ratio on the PC2-5300?As a note, I tested my system with geekbench and found that my system is a bit faster in general except for writing to the ram and it seems the RAM is clocking at DDR-790. I'll be testing the memory overnight but it would be great if you guys could let me know if it'll be fine.I just got my first lockup. Still testing around with different bios settings. Anyone with P5W-DH has the same setup?