What should the refresh cycle timings be for each dimm on a 2x2GB DDR2 system? According to CPU-Tweaker, mine are set at 127ns-75ns-75ns-75ns (the first 2 numbers are my populated slots). Should I leave it that way, or turn them both to 127ns or both to 75ns or what?
It completely depends on the memory. What is the memory spec'd to run at? Memory comes in many, many timing variations. In fact, that is one of the most important things you look at when you buy memory.
Most memory chips have an eprom on them that tells the board that they are plugged into what the timings should be set at, and the board does it automatically. So, you need to find out what exactly your particular memory is supposed to be running at according the manufactures specifications, and then you will know if the board has the timings set correctly.
I have G.Skill Trident DDR2 1200 and I can't find anything more than what cpu-z shows me on the spd which is 533 @ 5-5-5-15-48-2T @ 1.8v.
I currently have it stable at 544 @ 5-5-5-5-16-2T @ 2.1v. The issue is that on another forum (OCN) was saying that my dimms were running at 127ns and 75ns, which they are. He mentioned that in his experience, 75ns is for an unpopulated slot, 127ns is for 2 populated dimms and and 195ns is for 4 populated slots. I have been unable to find much on this so I'm asking you guys.