Is there an ideal FSB:DRAM ratio?

projects14a

projects14a

projects14a

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Have searched and searched for this, but cant seem to find a definative answer. Ive also tried asking in a related thread i started in the memory forum, but still no answer.

Is a 1:1 ratio better than 2:3, 2:4 etc etc? Ive read that people like to use the 1:1 and aim to keep that way, but does it actually make any difference, or does it just keep things simple?

Many thanks!
 
1:1 ideally but DDR2 is the issue as if you get a good Mobo with a really high FSB your approaching DDR3 speeds.

Example a peep with a Mobo at 600FSB (2400FSB QP) that's 1200mhz Memory speed needed, it can be done on DDR2 but hard to get 2GB Modules to do it.
 
I see, and the limiting factor will obviously be how much the DDR2 can be over clocked.

This now leads me to another question, does it matter if i then lower my multiplier for the CPU or is there an ideal for this too?
 
1:1 is seen to be the best...but.... it all depends on what gives you a speed boost! i've seen people with 5:4 ratios getting better benchmark scores than my 1:1
 
projects14a said:
I see, and the limiting factor will obviously be how much the DDR2 can be over clocked.

This now leads me to another question, does it matter if i then lower my multiplier for the CPU or is there an ideal for this too?
Click to expand...

Lowering Multi only means less Final MHZ overall (ie 3GHZ over 4GHZ), it will still be the same FSB so yes the Memory is the limiting factor.

Also going above 1:1 can get gains in benches and some Apps where Memory Bandwidth matters.
 
Last edited:
El Jimben said:
1:1 isn't necessary the best according to this - http://www.overclock.net/intel-memory/193449-memory-dividers-latencies-bandwidth-explained.html
Click to expand...

A good read but he's missing the point a bit with the ratios.

Yes 2:3 and 1:2 is faster than 1:1 cause the memory is running so much quicker and is no more than I expected.

However, assuming that with fsb and mulipliers you can get any combination you want for a minute, the big question is does memory running at 400Mhz with a 1:1 ratio faster than running at 400Mhz with a 1:2 or 4:5 ratio?
 
Thanks for the info! Will have a read of that and hopefully will clear up a few things in my head :)

Ive just tried to replicate my current clock of:

FSB: 320
Multi: 9
CPU : DRAM: 1:1.125

Resulting in 2880Mhz CPU and Memory at 400Mhz

With this:
FSB: 400Mhz
Multi: 7
CPU : DRAM: 1:1

Resulting in 2800Mhz CPU and Memory at 400Mhz

But unfortunately hung on OS start up. Im guessing the chipset will need a boost for the increased FSB? Would this be MCH (NB), ICH (SB Core) or ICHIO (SB IO Channels)?

I dont think its memory related as its running the same speeds, but could i be wrong?
 
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