ram ddr2 1000 vs 800?

Well, if everything is exactly the same, then the ram itself is 20% faster. Of course, the timing is usually slowed down when megahertz are increased.

Examples: A 1000mhz RAM stick w/ 4-4-4-12 timing will be 20% faster than an 800mhz RAM stick w/ 4-4-4-12 timing, but they will usually cut the timing down to a slower 5-5-5-15 (or something similar), so if that's the case they will be almost exactly the same speed. It's just a dirty marketing trick.

Now, obviously you want to know how much faster it will make your computer. As they say, a computer is only as fast as its weakest link. So if the RAM is the bottleneck, then you will feel the full effect of the upgrade. But if something else like the CPU is slowing down your computer, then upgrading your RAM might not make that much of a difference.

4 gigs of ddr2 800 would be extra perfect then 2 gigs of ddr2 1066, yet out of the two possibilities 4 gigs of ddr2 1066 is the final, uncomplicated exchange in cas shouldnt make to special of a transformation, if ur reminiscence will artwork with tighter timings than 4 is the alternative.