Hi to geokholer, or anyone can answer if knows a solution to this. I just read a older post from few years ago as I'm interested in upgrading my vaio laptop fz11z. got cpu t7300, 800mhz FSB, chipset intel pm965, vista 32. I did upgrade my Ram memory from pc2-5300 2x1gb 667mhz to corsair pc2-6400 2x2gb 800mhz. Surprisingly, despite upgrading my chipset drivers to the latest from intel support website, my system still runs the new memory at only 667mhz instead of the new and the much expected 800mhz. After a lot of internet research, looks like Intel is throttling the frequency of my ram to 667mhz to prevent overheating, and I think this can be changed somewhere in Bios, but I cannot acces any parameters or settings under bios memory panel, also cannot find any upgrade for my bios and I don't know if this update exists or it will solve the ram frequency issue. Any solution to that? You (geokholer) claimed in your post that the system should recognize de memory. Cpu-z test sees that the true memory frequency is 800mhz (aka 400mhz per channel) but is also showing that is running only at 667mhz (330 per channel). Should I try another brands of similar memory (I guess will be same result)? And another question, if I switch to Windows 7 64 bit version (in order to use all the new 4gb RAM), will the same drivers from Sony support work (those are designed for vista x32)? Also you said that you are a guru of intel pm965 chipsets and stated that the new memory upgrade should be cas latency 4 (I couldn't find anywhere such thing, the best is cas 5 for sodimm 200pin pc2-6400 for laptops) and memory should be low density 128x8 not 256x64 (despite all the memories on the market -2gb per unit- being actually 256x64! and having 128x8algorithms included so I am a bit confused about what you tried to say, sorry!). Thank you. Adrian, London.