Page 1 of 1

Newb Question about C2D desktop RAM

Posted: Thu Dec 06, 2007 4:43 pm
by JMEaT
Chipset: Nvidia 650i
Proc: Intel C2D E6600
RAM Speed: 800MHz (240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)
Frontside BUS Speed: 1067MHz

Shouldn't the RAM run at the same speed as the FSB? O.o
Image

I know the RAM speed is DDR2 800, but should I have DDR2 1067 in there? Or is this different on Intels?

Posted: Thu Dec 06, 2007 5:02 pm
by JMEaT
Hmmm, upon searching, 800MHz seems like the fastest this board supports, so I guess this is by design.

Used to AMD's :P

Posted: Thu Dec 06, 2007 6:51 pm
by Krom
Yes, that is normal and as it should be. The real \"FSB\" frequency of your C2D is 266 MHz, the C2D (and the P4 before it) uses a quad pumped bus.

Also this means your RAM is running at a multiplier to reach 800 MHz rather than the actual bus speed. If your RAM was running 1:1 with the FSB it would actually be at 533 MHz. To reach 800 MHz your ram is running at a 3:2 ratio multiplier to the FSB.

So:
266 * 4 = 1067 MHz rated FSB.
266 * 6-9 = 1600-2400 MHz CPU core.
266 / 2:3 = 400 DDR = 800 MHz RAM.