Your best timings with Crucial "8T" single-sided

[Otter]

Hello all.

I think this RAM <a href="www.newegg.com/Product/Product.asp?Item=20-146-541&depa=1">CT6464Z40B.8T</a> is rated at 3-3-3-6 by Crucial, but I've heard rumors of people managing 2-2-2-x 1T. I'd like to hear from anyone who has a pair of these and has tried to push them beyond spec for low latency. Don't be shy if you took them below 200MHz to get better timings; I might do that too. Please post your mobo, cpu, and ram clock along with your timings.

I'm thinking of using four of these because they're single-sided (allowing 1T with Venice according to AMD) and cheap. But if the timings can't be narrowed, it's probably worth the extra $60-$70 bucks to me to go with a low-latency 2x1GB solution.

While I'm thinking about four of these sticks for my system, I'll be very happy to hear about results with two sticks. It would be great to hear from someone with the exact setup I'm contemplating, but I don't think that's very likely, so tell me about your 2x512MB system. But please post only results for single-sided RAM in this thread.

Thanks.

[pelikan]

My 2 x 512mb does 245, 3-3-3, with 2.8V.

[(sin)morpheus]

I don't believe you can get 2 2 2 x timings on those sticks. Unless you get some magical ones or something.

[Otter]

Thanks Pelikan. Have you ever tried to get below 3-3-3? Your overclock is pretty good bang-for-buckwise, and I gather that quite a few people have managed 240 with this RAM. But I'm more interested in low latency since I read this thread
http://forums.anandtech.com/messagev...VIEWTMP=Linear

About the middle of it, Zebo says:

Another good one is crucail 8T Here
http://www.newegg.com/app/ViewProduc...146-541&depa=1

Users like Pelikan have gotten 3-3-3 up to 250Mhz and of course 2-2-2@200

Which seems to indicate you (or someone like you) managed 2-2-2@200. Is this true? Or do you think that "of course" was probably based on results with Crucial modules using lower-density chips?

[SnipingWaste]

I have tested some stick of the same ones you have and was able to do 220 2.5,2,2,5,T1 at 2.65V. The other stick was bad and RMAed. To Realy get good timming and HTT you will need to use 3.0V to 3.3V with ramsinks and fan. With all that you should be able to do 250 2.5,2,2,5,T1.

[poiuy223]

all your results should vary depending on the actual IC's used. currently that i know of, crucial's pc3200 widely uses -5b C, -5b D, and -5b G. there are E and F but they've been found to be crap. C is used in OCZ's EB line and were great. could do 2.5/3-2-2 near 280MHZ with increased voltage. G is used in their ballistix line and gets similar results but dont respond as well as the C with increased voltage. it can do 2-2-2 though. D is the lowest grade, and IMO, sucks. i have some that are 512mb and single sided. lowest it goes is 2.5-3-2, with any voltage up to 3.2v. with 3-3-3, it did go to about 240-250ish with 2.8v. it was too "cheap" for me so i didnt waste my time testing it

[Reefa_Madness]

Aren't the EB, and now the Ballistix, double-sided 512MB sticks?

They use the same Micron chips, except that the Micron chips used in the ".8T" Crucial are 8 of the 46V64M8 vs 16 of the 46V32M8 used in the EB and the Ballistix.

I had this discussion sometime back last summer when one of the guys over at OCF got a set of the ".8T"s. Crucial made a Double-Sided 512MB stick and its product code ended in ".16T" and was made with 16 of the "46V32M8" chips just like the EB.

[poiuy223]

no EB and Ballistix do not use the same chips, not exactly. they have different revision. the "C" and the "G" sets it apart. the "G" is the one that allows 2-2-2. as for double or single sided, so far it doesnt really matter. theoretically, single sided is better because of the lower number of IC's used. but then you also have denser chips which can cause lower overall overclock. so right now, it shouldnt really matter between single or double sided

[Reefa_Madness]

no EB and Ballistix do not use the same chips, not exactly. they have different revision. the "C" and the "G" sets it apart. the "G" is the one that allows 2-2-2. as for double or single sided, so far it doesnt really matter. theoretically, single sided is better because of the lower number of IC's used. but then you also have denser chips which can cause lower overall overclock. so right now, it shouldnt really matter between single or double sided

Yes, I know about the "C" and "G" and should have clarified that they were not the same revisions, but what I was trying to focus on was that the density was different on the single sided ".8T" vs the double sided ".16T" (or the OCZ EB and the Ballistix).

So am I correct in stating that, in your opinion, the single-sided "advantage" is offset by the chip density and therefore no difference in performance should exist between an 8-chip single sided 512MB stick and a 16-chip double sided one?

Crucial is about the only one that I can think of that makes single-sided 512MB sticks and I've always been curious as to whether there are advantages or not with going that route.

[pelikan]

Thanks Pelikan. Have you ever tried to get below 3-3-3?

They won't do low latency. I've tried as low as 200 MHz. But I've never given them more than 2.8V so who knows?

[poiuy223]

So am I correct in stating that, in your opinion, the single-sided "advantage" is offset by the chip density and therefore no difference in performance should exist between an 8-chip single sided 512MB stick and a 16-chip double sided one?

unless they make exact same perfect high density chips, pretty much yeah.

[Otter]

So am I correct in stating that, in your opinion, the single-sided "advantage" is offset by the chip density and therefore no difference in performance should exist between an 8-chip single sided 512MB stick and a 16-chip double sided one?

Crucial is about the only one that I can think of that makes single-sided 512MB sticks and I've always been curious as to whether there are advantages or not with going that route.

I would think the 16 chip version would give better performance if there were only two sticks. Density seems more important than the other factors, and I reckon that's why 512MB single-sided RAM is so rare. I suspect Crucial might be producing this RAM to get rid of chips binned out of some other program -- maybe 1GB Ballstix.

With four sticks, I'm not sure. Four double-sided DIMMs means 2T (3%ish hit) and perhaps a lower clock speed. But failing to find any affordable, high-density RAM that reliably reaches decent timings, I'm starting to wonder if i wouldn't be better off going with four double-sided sticks.

[Otter]

all your results should vary depending on the actual IC's used. currently that i know of, crucial's pc3200 widely uses -5b C, -5b D, and -5b G. there are E and F but they've been found to be crap. C is used in OCZ's EB line and were great. could do 2.5/3-2-2 near 280MHZ with increased voltage. G is used in their ballistix line and gets similar results but dont respond as well as the C with increased voltage. it can do 2-2-2 though. D is the lowest grade, and IMO, sucks. i have some that are 512mb and single sided. lowest it goes is 2.5-3-2, with any voltage up to 3.2v. with 3-3-3, it did go to about 240-250ish with 2.8v. it was too "cheap" for me so i didnt waste my time testing it

Do I understand correctly that it's pretty much a crapshoot what chips you'd get in a set of Crucial 8Ts? That would explain why a few folks seem to get pretty good performance out of these while others report results like yours above.

[robberbaron]

They won't do low latency. I've tried as low as 200 MHz. But I've never given them more than 2.8V so who knows?

Yeah, well, Micron memory loves voltage, so you didnt really push the ram much.