Speed vs latency

[atigger]

Hi I didn't have the time to go throught all of the old posts for the answer to this. So generally for memory you the speed (PC3200, PC4000) and latency (timings 222 232). And for higher speed memory that you buy it generally has higher latency because it is harder to make. However, say I buy CMX512-3200C2PRO XMS3200 512MB 2-3-2-6 and CMX512-4000PRO XMS4000 512MB 3-4-4-8. Clearly one will be able to run faster if I OC my bus/memory. However at the same speed, say 400mhz, which will have lower latencies? Will I be able to set faster timings for the PC4000 or for the PC 3200 and how would I normally know this?

 

[ytoledano]

You wouldn't buy it doesn't really matter, noone buys DDR500 to use it at 200 FSB and really tight timings, and even a really small increase of the FSB would make the system faster despite bad timings.
If you must know, 2-2-2-5 are the best timings there are and 2-3-2-6 isn't far away so how much can you OC the timings on a PC4000?

Is 2^33634943-1 prime? (more than 10Mil digits @65.11) I will know in 10 days when <A HREF="http://www.mersenne.org" target="_new">Prime95</A> finishes checking!

 

[scottchen]

PC3700, PC4000, PC4200 aren't designed to run at low latencies, some of them may not run anything but 3-4-4-8 at any frequency. OCZ's PC4200 Performance series is an example. It works at 266mhz, 3-4-4-8, it works at 200mhz 3-4-4-8, not 200mhz 2.5-4-4-8, so it's meant to run at high frequencies not tight timings. What's the rest of your system, and how high are you planning to overclock. If you buy anything beyond PC3200 then it's obvious you're planning to overclock.

-Intel PIV 2.6C @ 3.575G -Asus P4P800 -OCZ Copper 2x256 4000EL memory @ 275mhz 3-4-4-8 -XFX 5900 128meg 450/900 -SB audigy -120G Maxtor Diamond Plus9 S-ATA150 hdd -450 Enermax PSU

 

[atigger]

=p yea I just can't decide. I probably wouldn't overclock all the time, so I guess I want PC4000 just so i can mess around and see how fast i can get it once or twice for a benchmark. However, if this is going to mess up my performance at regular speeds (PC3200) because of high latencies then I guess it's not worth it.

 

[jammydodger]

Apparently P4's benifit from faster memory, while Athlons much prefer tighter timings. Im assuming this is because the FSB of the Athlon it too low to take full advantage of anything above 400mhz let alone dual channel RAM.

Why use windows when you can use doors?

 

[ytoledano]

You shouldn't look at overclocking as "the fastest a system can go but unpractical in day to day use". It would take you little time to find your system's "sweet spot" where it's as fast as it can be while 100% stable, and as long you don't increase Vcore more than a little (or at all if you want to be very safe) you won't risk long-term damage. Faster RAM eliminates it as a bottleneck.
Note that the above is correct almost always but on rare cases you can harm your computer or have your system become unstable after stress-tested for 24 hours.

Is 2^33634943-1 prime? (more than 10Mil digits @65.11) I will know in 10 days when <A HREF="http://www.mersenne.org" target="_new">Prime95</A> finishes checking!