1FSB:1RAM Question About Memory Speed When Overclocking

handsome

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May 15, 2007
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Quick question i've read a lot of people say to set the DRAM Frequency to DDR@ - 533 on a P5B Deluxe this will result in a 1:1 ratio with the fsb and the ram. my question is if the fsb is say 334mhz and the cpu multiplier is 9 to achieve a cpu speed of 3.0GHz that means that the memory will run at 334 mhz as well but my ram is ddr2 800 so it runs stock at 400 so the cpu is overclocked but the memory is underclocked right? is that going to hinder performace or should i go with a 400 fsb at a different mulitplier? Just asking because i've read that you can achieve lower vcores with smaller fsb's which should reduce temp. I just want to over clock my e6600 to 3GHz with a asus p5b deluxe wifi/ap and 2 gb (2x1gb) corsair xms2 ddr2-800 ram but achieve the best results with lowest temps thanks for the help!
 

kbk_75

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Aug 5, 2003
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Your DDR2-800 will be running below spec if your FSB:Mem is 1:1 and your FSB is 333. While that's not ideal, it's not a major issue either. All it means is that you aren't fully utilising your RAM bandwidth. You can try to tighten-up your memory timings a bit since you're running below-spec.

Alternatively, if you want to do 3GHz, you would need FSB 375 with a multiplier of 8 or FSB 429 with a 7 multiplier. Whether or not your motherboard / cpu / RAM will take it is another matter.
 

aLdaRiS

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May 4, 2007
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yup exactly, ie. my ram is pc6400 ddr2 800 5-5-5-15, and im runnin it ddr2 667, 4-4-4-12, i might even be able to squeeze sum tighter times, but to be completely honest, i rather leave it like that since its pretty stable, rather than doing 400fsb x 8(multiplier) runnin @ 3.2 and havein my ram run @ ddr2 800, cos even tho i might be wasting a lil bit of my ram, i cant REALLY tell.
 

jordanwise

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Dec 7, 2006
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EXACT same componants as you. Am i right in guessing that when you set your ram to (effective) 800mhz the computer doesn't boot? i've had this problem for a few months, its apparantly due to a fsb strap at 333mhz fsb or summat, i'm not into such technical matters though and never had i fully explained
 

aLdaRiS

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May 4, 2007
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actually it does boot, its just that ive heard a lot of ppl say that runnin 1:1 fsb:ram, its the most stable way to overlcok, and even tho my memory does boot @ 800mhz its not as stable :]
 

conrad357

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Jul 13, 2007
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i'm in the same boat with 6400 ram and can't get it to run at full potential, so then just do 333 or 1333 fsb and manually set ram to 667 and tighten timings?
 

Hatman

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Running the Bus Speed the same as the RAM speed usually works out with better performance within a small margin and overclocks a bit better. But for overclocking its best to lossen your RAM timings a lot, overclock teh CPU as far as it'll go, and THEN try to tighten the timings.