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View Full Version : Asus P4PE and Corsair vs. Micron...


cvearl
04-07-03, 02:58 PM
I need to ask the hardcore guys a question.

Recently, I was able to exchange my 4 month old Crucial(Micron) PC2700 CAS 2.5 DDR memory (2x256MB modules) for Corsair XMS PC2700 CAS 2.0 DDR (2x256 Modules). I did so only because I have a friend that runs a high performance computer store and he helped me out. I only had to pay $15 in the exchange. He's a nice guy. I took them home and removed them from the beutifull packaging. They are the coolest looking RAM modules I have ever seen. Heatsink and all.

Anyway, the other reason I even went through the trouble was because it was supposedly a lower latency product than the Micron as is supposed to be the "Fastest in the World" for it's class of memory anyway. Now I know that you normally only need Corsair stuff if you are an overclocker but I thought that even with the lower latency stuff I would get a tiny boost even when at stock clocks for my motherboard but using the recommended CAS settings for the Corsair.

Here's what floored me...

The Micron (labeled Crucial) is faster across the board! In testing with this P4PE motherboard, I tested both with the DRAM timings set to "SPD" mode. In which case the motherboard goes by the internal register of the RAM which by JEDEC standards is CAS settings of 2.5-3-3-7. Both sets of memory say this in the BIOS when left in the "set by SPD" mode. At this setting, I get the following results...

in 3DMARK2001SE...

Micron PC2700 2 x 256MB modules - 13,651
Corsair XMS PC2700 2 x 256MB modules - 13,540 (lower by 111 pts)

In Sisoft Sandra memory test...

Micron - 2568
Corsair - 2538 (lower by 30 pts)

So ok, I say to myself. Sure but what about when I set these babies to the recommeded latancy timings! Which are 2-3-3-6.

3DMARK2001SE - 13,589
Sisoft Sandra memory test - 2556

Both results are still lower than the Micron at stock settings. Even if I set my motherboard to TURBO mode, I still cannot reach the 3dMARK or Sandra scores!

Moral of the story? Don't be sucked in by brand names or false claims of performance. I do know that the Corsair would allow me to push my FSB farther than the Micron stuff but I am not an overclocker so that is not much of a selling feature to me. So what did I gain getting these Corsair units? Brand recognition and as a result Resale value I guess.

Anyone else see this sort of thing before?

Charles.

Riptide
04-07-03, 03:57 PM
That is strange. That Corsair XMS PC2700 should be defaulting to 2-3-3-7, not 2.5-3-3-7. I have the exact same motherboard / memory combo and mine defaults to CAS2 on SPD... You might want to check the part number on that RAM against what Corsair has on their site just to check...

cvearl
04-07-03, 04:07 PM
Originally posted by Riptide
That is strange. That Corsair XMS PC2700 should be defaulting to 2-3-3-7, not 2.5-3-3-7. I have the exact same motherboard / memory combo and mine defaults to CAS2 on SPD... You might want to check the part number on that RAM against what Corsair has on their site just to check...

Are you kidding me????????

Damn!

OK, in my BIOS, in the Chipset Features area, If I leave the first DRAM setting to "By SPD", the CAS settings are greyed out (are yours displayed yet greyed out as well?) For me they say 2.5-3-3-7. This could indeed be cause for alarm. Perhaps the wrong modules??? They are supposed to be this...

http://www.corsairmicro.com/main/products/specs/cmx256a-2700c2.pdf

Is that the same as you?

It will run a little faster if I change SPD to MANUAL and go 2-3-3-6. But I thought that the SPD would pick up the settings anyway.

Let me know. Thanks...

Charles.

Riptide
04-07-03, 05:46 PM
No, I'm not kidding. I'm like Egon from Ghostbusters: I'm always serious. ;)

My settings are grayed out as well when in SPD. That is normal when you choose SPD.

Wish I had my PC in front of me right now because I'm at work and can't see what the settings are, grayed out or not. I believe they are @ 2 and not 2.5 though, to the best of my recollection.

Regarding the link you posted, those are my same DIMMs but I have the 512meg version. You can see a link here, coincidentally from where I purchased them @ a great price:
http://www.googlegear.com/jsp/ProductDetail.jsp?ProductCode=80060

Not sure what to tell you... Do they run stable when you manually set them to CAS2? They *should* default to CAS2 on SPD. Not sure why they aren't...

cvearl
04-07-03, 06:02 PM
Originally posted by Riptide
No, I'm not kidding. I'm like Egon from Ghostbusters: I'm always serious. ;)

My settings are grayed out as well when in SPD. That is normal when you choose SPD.

Wish I had my PC in front of me right now because I'm at work and can't see what the settings are, grayed out or not. I believe they are @ 2 and not 2.5 though, to the best of my recollection.

Regarding the link you posted, those are my same DIMMs but I have the 512meg version. You can see a link here, coincidentally from where I purchased them @ a great price:
http://www.googlegear.com/jsp/ProductDetail.jsp?ProductCode=80060

Not sure what to tell you... Do they run stable when you manually set them to CAS2? They *should* default to CAS2 on SPD. Not sure why they aren't...

Haha, I was at work posting this.

Anyway, if it is not too much trouble, can you double check for me tonight?

Charles.

Riptide
04-09-03, 10:52 AM
Just rebooted and checked the BIOS. Set to SPD and the settings show up as 2-3-3-7 and are grayed out...

I would check your part # if you haven't already, just to be thorough. See if it is printed anywhere on the heatsink.

cvearl
04-09-03, 11:54 AM
Originally posted by Riptide
Just rebooted and checked the BIOS. Set to SPD and the settings show up as 2-3-3-7 and are grayed out...

I would check your part # if you haven't already, just to be thorough. See if it is printed anywhere on the heatsink.

Hey thanks man! I will check tonight. Also, Corsair suggested I reseat the memory and run memtest85 to make sure I am not getting any errors.

I'll keep ya posted. Thanks

Charles.