underclock DDR2-800 memory?

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jordo_99

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well i'm looking to overclock my AM2 X2 4200. i've got 2GB of XMS RAM at DDR2-800. i think the latency is 5-5-5-12 or 5-5-5-15. anyways my question:

if i were to lower the frequency to DDR2-667 from the stock DDR2-800 would i then be able to tighten my latency on my RAM and overclock my CPU more. i've never overclocked before i was just told that 5-5-5-12/15 isn't a very good latency and that i couldn't OC my cpu very much w/ that. so i figured...why not just slow down the RAM to speed up my cpu?

it really doesn't sound like a very good idea to slow down RAM...but yeah...idk...i'm just a stupid OCing noob.

any suggestions for me to OC my X2 4200? Thanks.

BTW my specs
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No, that would not be beneficial.

Also, keep in mind that "latency" is not just a result of timings, it is a product of both frequency and timings. DDR2-800 at 5-5-5-15 isn't really "high latency" RAM.

See the formula below:

There's more to memory latency than just the number like 2, 2.5, 3, 4 or even 5. Those numbers are clock cycles. This means the used frequency has a huge role in what those numbers actually mean:

frequency = oscillation(s) / second
and
1 oscillation = clock cycle

2 clock cycle latency at 200MHz (DDR400 CL2) in nanoseconds
= (1000 000 000ns / 200 000 000) * 2 (cycles)
= (10ns / 2) * 2
= 10ns

4 clock cycle latency at 400MHz (DDR2 800 CL4) in nanoseconds
= (1000 000 000ns / 400 000 000) * 4 (cycles)
= (10ns / 4) * 4
= 10ns

Length of a clock cycle depends of the frequency -> absolute latency (nanoseconds) on ddr2 is often even lower than on "low latency" DDR1 chips like BH-5, etc. For example:
Micron D9 DDR2 800 cl3 = 7.5ns
That equals BH-5 @ DDR534 cl2...
And DDR2 needs only 2.0-2.1V for that.

Other alpha timings?
On DDR2 800 tRCD and tRP can be as low as 2 clock cycles. Beat that with DDR1 (that would require tRCD/tRP @ 1 on DDR400). So, in the end, which one is lower latency? DDR1 or DDR2?

Source

I would also recommend doing some more reading on the subject before you jump in too far.
 
haha...i had to read over that twice to understand that, but i think i've got it now. thanks for the info. it really helped give me an idea as to how to get my RAM to optimal speed.
 
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