CPU/Memory matching information??

[lodrazor]

This may sound like a stupid question, but does anyone have a listing of what memory speed goes with each C2D cpu?? In the good 'ole days of DDR, it was quite easy, but now with DDR2 and DDR3, I am having trouble knowing what memory speed goes with each C2D cpu. Example: Do I need 533, 667, 800 mhz DDR2 for a 6600? I know it will run with 800, but what is the lowest speed required? Does that make sense? Thanks in advance for any assistance.

 

[apt403]

It'll run fine with pretty much anything. The ideal way to run ram is in a 1-1 ratio with the cpu. The FSB on all the E6xxx series that are available ATM is 266mhz, quad pumped to 1066mhz. DDR2 533mhz ram actually runs at 266mhz, but it can complete 2 operations per clock (DDR = double data rate ), making it's effective speed 533mhz.

My point is, if you're not oc'ing, use DDR2 533.

 

[nvalhalla]

Ram, with 2 sticks, runs twice as fast (called dual channel) as it's advertised speed (DDR2-800 RAM will run up to 1600MHz in dual channel). So, 2 533 sticks of RAM, running in dual channel, will run at 1066 with the FSB of the CPU. So, as long as you are using 2 sticks (or 4 sticks) you will be running in dual channel and only need RAM at half the speed of the FSB. Now, if you want to use only 1 stick you will want RAM equal to your FSB, in this case 1066 RAM. This is why people use 2 sticks (or 4 sticks), it allows you to use the cheaper, slower RAM and run it in dual channel, keeping up with the FSB. Make sense?

 

[nvalhalla]

DDR2 800 means the RAM is actually running at 400Mhz, not 800Mhz. The DDR2-800 designation is based on its effective data transfer rate, not clock speed.

If the 800 isn't the RAMs clock speed, then his FSB isn't 1066 either. His FSB speed is 266, quad pumped, the RAM is 400, I suppose you could call it double pumped. The advice given above still applies. The RAM, to run 1:1 with a 1066 FSB, only needs to be 667.