memory questions for A8N SLI 2x1024 or 4x512

[Sarcassimo]

im shopping around for potential memory upgrades. from what i can tell is that the A64 chips like tight memory timings like 2-2-2-5 1T and are not bandwith starved. id like to get 2 gigs of ram with reasonable timings like 2.5-3-3-8 1T or better. ive read that filling all slots forces a 333 fsb for the ram. not really bad actually but my main concern is that can i over clock it from there? and can i maintain a 1T command rate with 4x 512 memory? Twin MOS has some interesting "midline" 512 sticks TMSP400/512 2.5-3-3-5 1T that are on the QVL that arent real expensive. my other choice for 1 gig sticks would be something like Patriot PEP1G3200LL 2-3-2-5 1T (expensive) any thoughts or wisdom would be appreciated on this. after reading many forum posts i didnt find any solid information to clear this up. my system specs are in my profile. my first post lets not make it a BBQ. heh.



Sarcassimo

 

[imported_NoGodForMe]

I have two gig in my machine. It runs slight slower in the benchmarks with 2 gig versus 1 gig. It OCs the exact same.
I can take my Asus A8V up to 230mz, and that's where my road block is.
Your roadblock will happen at 245-250mz, that's just where people are getting stuck on the A8N.
I run my memory at 2336 timings, as it can't run at 2225.
I wouldn't worry about the timings as that doesn't make much of a differance.
If you wanted, you could go with Corsair Value select and it will probably OC up to 220mz. If you buy the good stuff, you'll probably get near 250mz, but that's where you will be stuck because of the MB.
If you wanna see what 2 gig looks like installed, go here and scroll to the very bottom of the page.
http://www.nogodforme.com/MyBabyTera.htm

 

[Sarcassimo]

i had taken the memory fsb limitation into account and planned on running the memory at the tightest possible settings near its rated speed possibly even underclocked. after reading the memory matrix post by zebo it clicked for me. my main concern was not taking the 2T command rate performance "penalty". on a side note the TwinMOS memory i mentioned is said to be Winbond UTT. the TwinMOS (or valueram) solution is certainly less expensive than 1 gig sticks with decent timings. im a bang for the buck guy one of the reasons i overclock. my machine gets used for gaming and some video encoding.



Sarcassimo

 

[JohnAn2112]

4x 512 will drop your memory speed to DDR333. Go with 2x 1GB so you can still maintain DDR400 speeds.

 

[zakee00]

Originally posted by: OCZ John
4x 512 will drop your memory speed to DDR333. Go with 2x 1GB so you can still maintain DDR400 speeds.

plus you still have 2 slots open for future upgrades...not that you will need them for a while 😉

 

[Visual]

Originally posted by: OCZ John
4x 512 will drop your memory speed to DDR333. Go with 2x 1GB so you can still maintain DDR400 speeds.

well thats such a lie... John, have you tried it yourself to claim so?
actually if you had read the previous poster's comment, you'd see he's running his 4x512 at up to 230 (DDR460)

4 sticks won't slow down the timings too, but i'm not sure about the command rate.
i hear 4 double sided dimms cause 2T, maybe if you get 512MB single-sided? anyway im just guessing.

NoGodForMe, it'd be good if you can tell us your command rate at 1gig and 2gigs, and if the performance difference is significant.

 

[Spikesoldier]

i have never seen a single sided 512mb dimm but i could be wrong and probably am

 

[Sarcassimo]

ive played with clockgen in windows some to see how far i can push the 2700 hyperx. 170 at 2-2-2-5 1T is it .. even when i loosened the timings it failed at 175. the cpu seems not to mind 2550 so far but ive not tested/pushed it much yet. considering im running the stock heatsink with an 80 mm fan + adapter its overclocking amazingly well. @ 2500 handled hours of gaming with no issues. if i was going to settle for 1 gig of ram id stick with the hyperx 2550 would be a respectable overclock even with the ram running at 170 but with tight timings. i had considered the purchase of 2 more 512 sticks of 2700 hyperx but if i was going to get my wallet out id like a little more headroom.


Squidlo

 

[Sarcassimo]

ive partially answered my own post with some research. yes there is a 2t performance hit with all 4 slots filled with double sided ram. ive messaged patriot to see if their 1 gig performance (PEP1G3200LL) is compatible with the A8N SLI motherboard.

in defense of OCZ John, yes it may default to 333 but if you raise the HTT of the processor you raise the speed of the ram as well. 166 + 64 = 230 and 264 x 10 = 2640 probably a very realistic scenerio with "value ram" (3200 winchester math).

im learning this stuff fast, thanks to the thousands of people working together, exploring and sharing information. if patriot says its a go.. i will let you guys know exactly what the 1gig sticks will do as far as overclocking and timings.



Sarcassimo