rambus memory

[Taurus]

i have an older system here that i'm updating and reformatting. it currently has 2x128mb of pc800-45ns rambus memory. i want to add on another 2x128 or 2x256 but don't know if other faster speed ratings would be compatible, like pc800-40ns? or can i run ECC memory at non-ECC?

also, what's the deal with 144mb and 288mb sticks??

 

[roirraW "edor" ehT]

Argh. I hate RAMBus (only because it's now rare). My brother's computer uses RDRAM and had 256MB originally but I lucked out and was given an otherwise useless computer which had 256MB more, so I gave it to him. I have no idea what the timings were on any of them, although I know they were PC800. If you like I can try to get him to find out the timings on his to at least let you know if he's successfully using two different ones.

My personal opinion, yes you can use a faster RDRAM like 40ns. Do you have a make and model of the system and/or the motherboard you can give? Even an older system like that there should be an online manual or at least other users' experience to guide you on the ECC versus non-ECC decision.

I would also try looking in the BIOS settings and see if there's anywhere to specify or where it detects whether it's ECC or non-ECC. If it does, then I would guess that it supports either, plus you might find out what you already have in there (I would add the same type as far as that's concerned).

Most systems come with non-ECC but RAMBus was different and I'm less familiar with it so I don't know what the norm was with it. I don't know about the 144/288MB sticks.

You may want to look at http://en.wikipedia.org/wiki/RDRAM and http://en.wikipedia.org/wiki/Rambus to see if they help you any.

 

[chastity]

Well whatever your going to do in regards to the RAMbus your going to pay a lot. Tigeredirect only has 1 listing and its 140 bucks and thats only for 2x128MB sticks. Generally you can't run ECC in non ECC systems because the pin count is wrong. As for faster then PC800 I think RAMbus made the pin count different so it can't be done.

As for the 144/288MB sticks does would be non standard sizes so even though RAMBus never took off they did use standard sizes in regards to the size of ram the stick's shipped in ie 128MB etc

For the cost of anything over 256MB is going to be steep, I believe over 300 for 512MB when I checked

 

[LeeJend]

"Add another 2x 128"? I thought RAMBUS only supported 2 sticks. There were issues with bus termination of the serial interface and stability.

You can get an inexpensive MB, 512M DDR2 RAM and CPU for less than you'll pay for the rambus memory. It was offensively expensive when it was at it's peak production and now it's essential out of production.

 

[Taurus]

thanks for the advice, guys.

ideally i would get the same exact spec memory that it already has, but like everyone already knows, they're not too common so i would like a larger pool to pick from. also, i will only be getting them off ebay as it seems they're quite expensive in stores.

i actually managed to recieve 2 different computers at the same time that both use rambus and even the same exact spec (pc800-45ns)...
- one is a dell with 2x128mb and 2 blanks. haven't actually gotten it fired up as i haven't gotten a replacement harddrive for it yet. it's a Dell Dimension 8200 and the board doesn't have any designation on it.
- other is a generic system with 2x128mb and 2x64mb. motherboard is an Intel D850GB.

i want to get 2x256mb and put it in the dell (slightly better) along with the 2x64mb for 640mb total. and then 4x128mb in the generic for 512mb total.

i just looked at the manual for the D850GB (didn't think of this :lick and it states a couple things...
- supports PC600 or PC800, but they all must be the same. doesn't mention ns ratings.
- supports ECC and non-ECC, but "If ECC functionality is required, all installed RIMM modules must be ECC-compliant." what if i don't want ECC functionaility? can i still use ECC-compliant sticks? if so, do all of them have to be? no clue. ECC rambus is as (if not more) common than non-ECC on ebay so it would be nice if i could mix.


also, i 'm now pretty sure the 144mb and 288mb i've seen refers to 144Mbit and 288Mbit, which denotes ECC.

 

[ray_gillespie]

Wow - if anyone ever wondered why RD-RAM never really took off they could just read this thread!

 

[Taurus]

Wow - if anyone ever wondered why RD-RAM never really took off they could just read this thread!

tell me about it. :dead:

 

[Taurus]

You may mix a pair of ECC (error correcting code) with a pair of non-ECC modules. This will cause the system to disable the ECC function of the ECC modules, make them function like NonECC modules.

i just found this out... from an ebay seller, no less!

 

[chastity]

Well I wish you luck with this. However I know the Intel 850 chipset or at least the Asus board I have with it has 4 slots, however I only have 256MB ram on it one 128 stick on each channel, sort of like how dual channel setups work but also have 2 crimms since its needed to complete the loop.

Ebay does have some 1GB RD Ram kits that are for dell's listed, and they seem cheaper then I've found anywhere else

 

[Taurus]

the 1gb kits are going for way more than i'm willing to spend on two computers that aren't even mine. like someone mentioned, you could get a new faster CPU/motherboard/memory for as much or a little more.

hopefully i'll win something on ebay this weekend and when i get them and pop them in, i'll update this thread with my findings.

 

[chastity]

Kinda of odd, as the one I'm looking at it not much more then the kit I saw listed on Tigerdirect if anything its actually less

http://cgi.ebay.com/Dell-Dimension-...ryZ11152QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[Taurus]

won a bid for Samsung PC800-45ns non-ECC 2x256mb (same exact speed and even brand as the existing memory) friday night, he sent it out saturday, and i got it today. three passes with memtest86+ with no errors so i'm happy. the previous sticks are single and get pretty warm... these new ones are double-sided and get HOT! damn near burned myself.

 

[roirraW "edor" ehT]

Ah, you're lucky you don't have a motherboard that has a problem with mixing single and double-sided memory, but maybe all RamBus-based motherboards are that way.

Glad it worked.

 

[ming]

Wow - if anyone ever wondered why RD-RAM never really took off they could just read this thread!

dont think anyone mentioned the 16-bit bandwidth on rambus compared to 32-bit on sdram... really big bottleneck.

 

[chastity]

glad you got it worked out, and I would guess the reason the sticks got so hot was because you stressed with more then you might normally

 

[Taurus]

glad you got it worked out, and I would guess the reason the sticks got so hot was because you stressed with more then you might normally

i first noticed the heat when idle at the dekstop and seemed just as hot as when testing. couldn't keep my finger on it for more than a quarter second.


thanks everyone for your help.