Corsair PC800 RIMM

Hi all.
My very first post on these forums is a question about Corsair RIMMS.

I've been waiting for an age for the release of the Asus P4T533 bundled with 256MB Samsung PC4200 to run a 2.26B. Release date is imminent. The disappointing news is that this board will now be supplied with 256Mb Samsung PC3200 instead because PC4200 doesn't look as though it's going into mass production until September although a date has yet to be officialy announced by Samsung. The same applies to 16bit 1066 Samsung RIMMs

Depending on the results of an independant review of this board using the supplied PC3200 I may still buy but if said review is not favourable one of my plan 'B' options is to get a tried and tested Abit TH7-II RAID and a 2.2A or 2.26B (undecided on the P4 for a TH7-II).

Now here's the crunch. I've read numerous threads that seem to indicate that the currently available 40ns PC800 from Samsung is difficult to overclock to 4x133 and that the earlier 45ns stuff overclocked with ease

Has anybody tried the Corsair 40ns PC800 rdram? Does the Corsair stuff overclock better than the current Samsung stuff? The general consensus is that Corsair make the fastest DDR memory, although some may argue - so does the same hold true for RDRAM?

I know Corsair is a pretty good company, and with their quality standards I'm sure it'd get close to 1066 speeds. I was reading a thread earlier... Ebolaman, here on the forums, has his PC800 Corsair at PC-1068 I believe.

You also have to remember that RAM is a lot like CPUs, some will hit the high notes, some will not.

Thanks for the reply. I've been looking at Corsair's site and these are the part numbers of the 256MB non-ECC sticks they supply.

CM616DR256A-800
CM616DR256A-800E - 40ns for I850E

Both parts are listed as 16Mx16 denoted by the 'A'.

Has anyone used these modules and if so, are they easily overclockable to 1066?

I have been able to get my Corsair PC-800 to run up past 1066, but not by that much. Oddly my highest FSB and best mem bandwidth numbers have been with two sticks of Kingmax 1066 and 2 Sticks of the Corsair PC-800 in the machine at the same time.

I presently am unable to get much past 178 FSB with my present set up, and I am starting to become convinced that the limit may not be the RAM but the CPU, because I have been able to run my memory at a muliplier of 4 up over 1100, but I do get anamalous results at the limits.

I need to put some effort into getting this thing to run with 1066 Memory only, something it has resisted this far. Then I will see what the story is. So far I would say the Corsair Memory is a good bet especially because it appears that that the TH7 doesn't know what to do with 1066 Memory. I have posted Memory bandwidth etc., marks elsewhere on the site, you be able to find them without too much difficulty.

Thanks, I found the screenshots you posted - very impressive scores
I'm SO tempted to get a TH7-II, 2.26B and Corsair PC800 now but I've been waiting so long for the P4T533, I guess 2 or 3 more weeks waiting won't hurt much.

Quick Q's: What are the part numbers of your Corsair sticks, if it's not too much trouble to take a peek? Also, does Corsair's listing of the above sticks as 16Mx16 mean that they are double-sided ie. 8 chips each side? Am I right in thinking that double-sided RIMM's are better overclockers?

WELCOME TO THE FORUMS

I run my Samsung PC800 RIMMs @ 1104 with no probs at all and it´s solid like rock!!

...did you read that one from NoobInside already ????

<quote>I run my Samsung PC800 RIMMs @ 1104 with no probs at all and it´s solid like rock!! </quote>

Thanks for the welcome and the link.
The link in the thread is for an article on DDR2700. Corsair are now using Samsung chips for their higher speed DDR and I suspect they're using Samsung chips for their RDRAM too. Seems kinda obvious seeing as Samsung are one of the very few manufacturers of RDRAM chips.
But if they handpick the best chips for DDR, surely they must do the same for RDRAM. The price would certainly seem to indicate this. Here in the UK, 256MB of Corsair PC800 is about 30% more expensive than 256MB of Samsung PC800.

Are your Samsung RIMMS double sided and are they 45ns? I've seen alot of threads indicating that the currently available (available in the UK) 40ns Samsung RDRAM is difficult to overclock to 1066 and in most cases impossible. It seems that people who bought the earlier 45ns sticks have had better luck
Am I right in thinking that the 45ns sticks had 16chips (8 each side) and the later 40ns sticks are single sided with 8 chips?

I'm thinking that the Corsair sticks listed above may be better overclockers than the current 40ns Samsung sticks because they're double sided like the earlier Samsung sticks.

Whooops! - You got me ! Well I know they´re double sided! But I don´t know if they are 45ns

Any ideas how to check that without taking ´em of my board and take a look on it?

It was so hard to put them in - I thought my pal (that build my system for me) ruined my board first !!

According to Samsung's site, if the part number ends with CK8 - it's 45ns. If it ends with CM8 - it's 40ns. The 40ns sticks are supposedly faster but I've heard they don't overclock as well as the earlier 45ns sticks.
Here's the link to the page on Samsung's site listing a few part numbers.

If you can see the part number on the sticks then that would be good to know but please don't remove them from your motherboard just to satisfy my curiosity. Based on what I've uncovered so far and the fact that you're running them at equivalent speed of 1104 then the chances are you've got the 45ns sticks.

Astronut said:

According to Samsung's site, if the part number ends with CK8 - it's 45ns. If it ends with CM8 - it's 40ns. The 40ns sticks are supposedly faster but I've heard they don't overclock as well as the earlier 45ns sticks.

If you can see the part number on the sticks then that would be good to know but please don't remove them from your motherboard just to satisfy my curiosity. Based on what I've uncovered so far and the fact that you're running them at equivalent speed of 1104 then the chances are you've got the 45ns sticks.

Click to expand...

Yes you are right!! I got the 45ns rams - it says -CK8 on the sticks! I only had to put on a flashlight and then I could see it clearly!

Well, anyways - according to the "Memory Bandwidth Benchmark" (SiSoft Sandra) my ram beats up all other reference rams!

The 45ns Samsung is very difficult to find now in the UK so IF I decide to get a TH7II I think I'll get the Corsair memory even it is more expensive. Latest news is the P4T533 board is starting to show up so I'll await the verdict on that board before I decide what to get.

After much fooling around I learned that my Corsair 800 is at least as good as my Kingston 1066 although unlike a DDR system mine runs better with more mem sticks than with less.

Ebolaman said:

After much fooling around I learned that my Corsair 800 is at least as good as my Kingston 1066 although unlike a DDR system mine runs better with more mem sticks than with less.

Click to expand...

Hmm, could be the secret to overclocking with RDRam...

By the way here is s screen shot of my best Sandra Mem Bandwidth.

Whoopin' the DDR.