AM2 Memory Characteristics

[996GT2]

So I posted some questions about AM2's RAM preferences a few days ago and didn't really get a definite answer. So I tested it for myself. I set out to test AM2's performance with 1) High Speed DDR2, 2 )Low latency DDR2 at lower speed, and 3) Performance gains from having a higher TRAS, as some people have told me. I also wanted to see the performance of Super Pi in Linux under wine, to see how much performance loss there was from the emulation. So here are the results:

*Keep in mind that while these times seem high, it is under emulation, so in Windows the time would be anywhere from 3-6 seconds lower.*

CPU Speed: 2.66 GHz, 1.34V
RAM: 2*1GB OCZ Gold DDR2-667, native latency 4-4-4-12
RAM Voltage was set for 2.1V in all the tests. 3 runs of SuperPi 1M were performed in each case,as well as 1 run of SuperPi 16M to test stability of the RAM.

SuperPi MOD 1.4 was used.

Test 1: RAM at DDR2-750, latency 4-4-4-12-1T
Average time, 34.8-35.0 seconds
http://img263.imageshack.us/img263/6576/dsc02142rk7.jpg

Test 2: RAM at DDR2-750, latency 4-4-4-16-1T (to see any gains from higher TRAS)
Average time: 35.0-35.15 seconds
http://img255.imageshack.us/img255/1336/dsc02144bi5.jpg

Test 3: RAM at DDR2-600, latency 3-4-4-12-1T (to see any gains from lower latency)
Average time: 35.8-35.95 seconds
http://img263.imageshack.us/img263/830/dsc02143ja6.jpg

So from these results, you can see that AM2 likes high speed RAM, in terms of RAW MHz. Lower latency helps, but not to the extent that extra speed does. Also, some have said AM2 has a preference for higher TRAS, but at least from my results it seems like a TRAS of 12 outperforms a TRAS of 16, though the difference is tiny.

Hope that helps.

 

[myocardia]

You forgot to say which version of SuperPi you were running. Each version gives different times, crazily enough. This one is what nearly everyone is using now: SuperPi Mod 1.5

edit: BTW, those times seem awfully slow. My Skt.754 3700 does better, for instance.

 

[996GT2]

Slow times are from emulation in linux as i said. In windows the time would be 3-6 seconds better. I wanted to test how much time was really lost by using Wine, however, so that's why I tested in Linux. 3-6 seconds seems like a lot for superPi but it's really pretty good considering it's being emulated.

I'm using version 1.4 MOD, you can see that in the top of the window in teh screenshot

 

[myocardia]

Haha, I remembered that when I first looked at the times. Then, by the time I posted, I had already forgotten about Wine. No wonder I like Beer better.😉

edit: I have pretty serious short-term memory damage. Keep that in mind.

 

[DrMrLordX]

Interesting, thanks for the results. Happily you were able to answer your own question as well.