Help with acheiving 1:1 memory ratio without a lot of OC'ing

sc10e

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Jan 3, 2009
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Hey guys, I am building a PC and will be installing a 65W AMD 5600+, 2.9ghz @ 200mhz x 14.5. I will be installing DDR2-1066 RAM.

I would like to achieve 1:1 ratio, but from what I have read (This is my first time building my own system and messing with any overclocking) I would need to raise the CPU's FSB to 533mhz with the RAM I am going to install, which seems pretty high, correct me if I am wrong. I am considering either underclocking the CPU's multiplier or the RAM, but I am trying to receive some benefit out of this, mostly keeping the full speed or more of the RAM and CPU. so I am not completely sure.

Any advice would be great. Thanks
 

50bmg

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Nov 16, 2007
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run the RAM at 800 and tighten up the timings.

400Mhz x 8 = 3.2Ghz or 400Mhz x 7 = 2.8Ghz. DDR2 ratio 1:1, Now you can tighten up your latency. I never have seen any real benefit out of OC'd ram.

any higher clocks will need a good cooler. Watch your temps and voltages with Hwmonitor, cpuz, etc.
 

sc10e

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So by 400mhz x 8 or 400mhz x 7 are you suggesting to reduce my CPU's multiplier to that?

Thanks for the reply.
 

sc10e

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uhhh...1:1 memory ratio means the motherboard doesn't have to run dividers on the RAM because frequencies match...
 

V3NOM

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and? thats less performance. just leave it at 1066mhz... faster than manually setting it to 800mhz to achieve the fabled 1:1 ratio... the point is anything ABOVE 1:1 ratio is BETTER..
 
AMD doesn't have a front side bus - the memory controller is on the CPU. As a result, there is no "1:1 ratio" - that's an Intel thing (and it is vanishing with the i7). Just go with some DDR2-800 and you'll be fine.
 

sc10e

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I already bought the 1066, I'll just run it at 800 and tighten the settings if need be.

Thanks guys
 

sc10e

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1:1 ratio aside though, is it better to have higher mhz with higher timings or lower mhz with lower timings?
 

V3NOM

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well timings to me don't seem to matter.
at 600mhz 6-6-6-18 i got 12000 3dmarks
at 600mhz 4-4-4-12 i got 12040 3dmarks
at 800mhz 6-6-6-18 i got 12300 ish 3dmarks
at 800mhz 4-4-4-12.... well that didn't work :p
 

patater

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search prior to post!! i know i put up a how to on this long ago...ok. anyways, where was i? oh yeah. ok, amd takes this new brisbane core and runs split multi like back in the day. bad for full ram speed. this is your formula again...

clock (200mhz or whatever) x multi (14, 14.5, 16...) = clock speed...
220mhz x 14.5 = 3200 mhz and 800 on the ram...

to formulate, since 14.5 is not a whole number, it rounds up...14.5/2 = 8 in this matter, not 7.25 (not the actual multi)

so remember, take whatever speed you want and plug in your numbers and seee what you get

i ran my 4000+ x2 at 230 x 10.5 and got 2.4ghz and 800mhz ram. but it doesnt really matter much for ram speed all that much. if you were running a quad it would kill it badly...