Dual channel memory and max cpu fsb

[airlessdavacuum]

So I'm overclocking my e6700 using the http://www.tomshardware.com/forum/240001-29-howto-overclock-quads-duals-guide thread. according to this it says not to exceed your memory's max fsb with ur cpu fsb. my memory is 1333 mhz g.skill 10600 2x2gigs. my cpu (again) e6700 @ 333fsb x10 multiplier. so my p5k3 deluxe, memory, and cpu are all at the same fsb which is where I want to be according to that overclock thread.

The real question is can I exceed that fsb with my cpu. I'm thinking because the ram is in dual channel I can but i'm not 100 percent sure.

 

[sportsfanboy]

Missed the bottom question... DDR means double data rate, so you set the ram to 333 in bios, it really runs at 666. Dual channel is something different, and deals with bandwidth, not speed per se.

 

[sportsfanboy]

If your going to keep a 1:1 ratio, you will need more than a FSB of 666mhz in order to go over your rams rated speed. That means you will literally need to double your overclock, before the ram becomes the limiting factor. I don't see that happening

 

[airlessdavacuum]

according to the thread i posted in the beginning, for ddr3 you take the mhz its rated at and divide by 4(divide by 2 for ddr2), mine is 1333. so divide that by 4 and I get 333. he is very specific when he says not to exceed that number for your ram unless you are trying to overclock it. This leads me to believe that ddr3 memory is supposed to be fsb x 4 = ram in mhz.

Not trying to be a pain in the ass, really trying to understand. cpu-z and everest both have me at 1:2 fsb:dram so i'm assuming you are right, just having trouble understanding why.

 

[sportsfanboy]

Like I said ddr is double data rate, not triple or quad data. So once again setting your ram to 333mhz in the bios will yield an effective speed of 666 when using a 1:1 divider. What he's taking about is IntelsFSB is quad pumped in your case. So Your fsb frequency is 266, it's actually 1066 effective. Or set to 333, it's 1333 effective. That is the FSB frequency not the ram.This does not change the relationship between the FSB and Ram. It's still FSB x 2 (double data rate) = ram in mhz when using a 1:1 divider.

 

[airlessdavacuum]

Like I said ddr is double data rate, not triple or quad data. So once again setting your ram to 333mhz in the bios will yield an effective speed of 666 when using a 1:1 divider. What he's taking about is IntelsFSB is quad pumped in your case. So Your fsb frequency is 266, it's actually 1066 effective. Or set to 333, it's 1333 effective. That is the FSB frequency not the ram.This does not change the relationship between the FSB and Ram. It's still FSB x 2 (double data rate) = ram in mhz when using a 1:1 divider.

awesome, thanks! so now I guess I have the options to increase my cpu and/or reduce the clock on my ram and try to reduce its latency timings. just for ultimate clarification, it would be pointless to increase my dram speed as long as my cpu fsb is 333 right.

 

[sportsfanboy]

You can try tightening the timings a bit or try overclocking the ram a little. I wouldn't kill yourself tweaking your ram as long as it's running at or near spec. Real world apps don't show a whole lot of difference with lower and slightly higher ram speeds. But in my opinion, can account for a good majority of system instabilities.

 

[airlessdavacuum]

Best answer selected by airlessdavacuum.