Memory make-and-model bandwidth comparison

BonzaiDuck

Lifer
Jun 30, 2004
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I want to get a better idea of which memory modules produce the best bandwidth for their speed rating specification.

As it suits forum posters -- and as they may be inclined -- please post:

Make and model
Number and size of modules
Your preferred stable speed setting (double-data-rate)
Your tCL, tRCD, tRP, tRAS, [command-rate], and tRC [bank cycle time] settings
Everest Ultimate, or [specified] other -- benchmark results

Also suggested: CPU and mobo make and model

I'll be posting my own results here soon, if anyone -- anyone at all -- expresses an interest.

This should also be of help to people looking to purchase the best modules offering the most in optimal possibilities for any number of over-clocking and tweaking scenarios.
 

Billb2

Diamond Member
Mar 25, 2005
3,035
70
86
Originally posted by: BonzaiDuck
I want to get a better idea of which memory modules produce the best bandwidth for their speed rating specification.

As it suits forum posters -- and as they may be inclined -- please post:

Make and model
Number and size of modules
Your preferred stable speed setting (double-data-rate)
Your tCL, tRCD, tRP, tRAS, [command-rate], and tRC [bank cycle time] settings
Everest Ultimate, or [specified] other -- benchmark results

Also suggested: CPU and mobo make and model

I'll be posting my own results here soon, if anyone -- anyone at all -- expresses an interest.

This should also be of help to people looking to purchase the best modules offering the most in optimal possibilities for any number of over-clocking and tweaking scenarios.
Not a good idea, for a number of reasons:
1.) Make and model are not enough info. In many instances the same "Make and model" may have different IC's (usually designated by Rev. No.), and will therefore behave quite differntly.
2.) The "overclockability" of a module also depends on the skill of the overlocker.
3.) What are "Stable" settings for one peson, may not be satisfatory for another.
4.) Even identical modules will overclock differently
5.) You make no mention of voltages.
6.) What memory? PC66, PC100, DDR DDR2, DDR3?

If it was a easy as you seem to think, to compile a list and choose the "best" memory, the reviewers would have been doing it long ago.


 

BonzaiDuck

Lifer
Jun 30, 2004
16,323
1,886
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Well, those are some good points. I came up with the idea "off the top of my head at 1AM. I would've mentioned voltage -- that's important. "DDR2" is important, although we're slowly moving toward a "DDR3 regime."

But I'm interested in bandwidth in connection with "tweaking" versus "over-clocking." Especially, your item #2 is a pretty big wild-card.
 

Billb2

Diamond Member
Mar 25, 2005
3,035
70
86
"I want to get a better idea of which memory modules produce the best bandwidth for their speed rating specification."

"But I'm interested in bandwidth in connection with "tweaking" versus "over-clocking."

All modules with latencies set the same and run at the same speed will have the same bandwidth. OCZ'a CAS 3 is the same timing in nanoseconds as GSkill's CAS 3.
The difference is that some IC's will run on a 200mhs buss with CAS at 3 and some wont. If they won't, then they're DDR2 533 (they may overclock, but not to DDR2 800. maybe 799, but not 800, cu'z if they went to 800, they'd be sold as CAS 3 800).

So, to answer your second question, if by "tweaking" you mean latencies, and by "overlocking" you mean buss speed then lower latencies and/or higher buss speeds will yield wider bandwidth. I know what you really want to know though. "Does 4,5,5,5, at 800mhz have more bandwidth than 3,4,4,4 at 533mhz...just test your sticks and see! Ah! but you say how will I know if the sticks I buy will run those speeds and latencies? You won't, until you try, and neither will anyone else.

If you want good memory, spend the time (and maybe the money too) and find someone that binns modules and then binns the sticks.
Other than that, it's a crap shoot if you're seeking those golden sticks, as most everything, except possibly some value ram, has already been binned so it won't be any better than the next highest speed the manufacturer sells and you can just go to the egg and point n' shoot. The manufacturers know what they're doing, most OC'ers don't... (yes, double entendre). There are 31 timings that can be set for memory modules, not just the 4 or 5 most OC'ers know. Go read the "white papers" and design criteria at AMD or Intel, or the JEDEC memory specs. Have a look at:
A64Info http://www.xtremesystems.org/f...showthread.php?t=96678
MemSet http://www.overclock.net/attac...set-3-0-memset30.zipor
Thiaphoon Burner http://www.softpedia.com/get/T...Thaiphoon-Burner.shtml
SPDTool http://forums.techpowerup.com/showthread.php?t=20349

Think about it. Where do the WR holders get their memory?...not from the egg. It's custom built by the manufacturers and handed out for "testing" or "comments" and (wink, wink) just happens to find it's way into hwbot scores.
It's all an advertizing game.

Team-xtreem. They're kind'a the Chip Foose of memory (sometimes!). http://www.teamgroup.com.tw/xt...treem/team-xtreem-ram/
 

BonzaiDuck

Lifer
Jun 30, 2004
16,323
1,886
126
I was lucky with my Crucial Ballistix DDR2-1000s. I didn't buy them to run at that speed, or even at 800 if the processor and the board limited me to CAS 4 and RAS 10, but I was gambling that they would be "downwardly elastic" to much tighter latencies. I knew some time ago that you could get some modules rated at a lower speed, and you could twist them up within the warranty voltage and still keep the very tight, stock latencies. This exercise has been a gamble in the opposite direct.

I'm still looking into this further -- right now, testing a tightened bank-cycle-time for stability. I'm even wondering if the "synthetic benchmarks" really show anything about this sort of performance, but I was stunned at how it performs. Almost had a heart-attack today on one of the "difficult" racing tracks playing "TrackMania." My Porsche is smokin'!

The way it looks, I'm going to drop the clock on my Q6600 B3 and cut the voltage so that it runs 50 Mhz slower. then -- wait and see what happens with the Penryns.

Generally, it's those wonderful Micron D9 parts, but there are several flavors, and you can never be sure which ones you're getting.

the "catch-22" is that many of us are between XP and Vista, and between 32-bit and 64-bit OS choices. You can either buy 2x 1GB and add 2x512 and lose the faster command-rate, or you can find 2 x 2GB, whereupon you have to hurry yourself into a change of OS.

But I suppose that's what "enthusiasts do." Cut back on the booze and cigarettes, conserve on gas-money, and buy parts! :D