Rambus RDRAM 400MHz available and worth it?

[Tim Mavers]

A friend wanted me to help him upgrade his Dell Dimension 800 as he is not
computer-centric. Since he had a P4 1.3GHz, I thought it would be no
problem (I was thinking most-likely PC2100 DDR). After I opened the case
however, I found that he had 2 64MB PC400 Rambus RDRAM modules. Ack!

I have no experience with Rambus modules, while they are easy to install as
anything else, I am more concerned with being able to find them and what are
the limitations of it.

I found PC600 Rambus ram for $32 a module on Pricewatch:

http://www.pricewatch.com/1/33/2210-1.htm

That was the slowest Pricewatch had... Do they make PC400 any more? Can I
just put the PC600 in (2 256MB modules) in along with the existing 2 64MB
PC400 chips and work?

 

[Bob Knowlden]

A quick look at support.dell.com shows that the Dimension 8100 uses PC800
nonparity RDRAM. (What model is your chum's machine, really?)

I suppose that you could insert a pair of PC600 sticks, and all might run at
PC600. I don't know how much more expensive the proper stuff is, but it
might be a good idea to go with it.

I'd normally suggest going to www.crucial.com for a decent price, good
service, and good compatibility, but they don't sell RAMBUS. You can buy it
from Dell, at a price somewhere between outrageous and obscene. (Dell will,
of course, guarantee compatibility. That's worth something.)

Before you buy anything from a Pricewatch merchant, visit
http://www.resellerratings.com/. That will help you separate the reliable
vendors from the disreputable ones.

HTH.

Bob Knowlden

Spam dodger may be in use. Replace nkbob with bobkn.

 

[S.Heenan]

A friend wanted me to help him upgrade his Dell Dimension 800 as he is not
computer-centric. Since he had a P4 1.3GHz, I thought it would be no
problem (I was thinking most-likely PC2100 DDR). After I opened the case
however, I found that he had 2 64MB PC400 Rambus RDRAM modules. Ack!

I have no experience with Rambus modules, while they are easy to install as
anything else, I am more concerned with being able to find them and what are
the limitations of it.

I found PC600 Rambus ram for $32 a module on Pricewatch:

http://www.pricewatch.com/1/33/2210-1.htm

That was the slowest Pricewatch had... Do they make PC400 any more? Can I
just put the PC600 in (2 256MB modules) in along with the existing 2 64MB
PC400 chips and work?

Both Samsung and Kingston make PC800 RAMBUS which should work in pairs on
that board.
http://www.valueram.com/config/type_parts.asp?type=rimm

You'd best check with Kingston for best compatability.

 

[Tim Mavers]

A quick look at support.dell.com shows that the Dimension 8100 uses PC800
nonparity RDRAM. (What model is your chum's machine, really?)

I was going by what SiSoft Sandra reported. I couldn't find anything on
the Dell site.. Even when we installed Dell's ActiveX control to scan the
machine to tell us what config we had. One would think that having an
express service code (or whatever they call it), you could see exactly what
was configured on that machine when it left the building, but I couldn't
find it. If anyone knows where that is, that would help, because if it is
indeed PC800, then I will need to get that.

Thanks,

 

[Tim Mavers]

Can

Both Samsung and Kingston make PC800 RAMBUS which should work in pairs on
that board.
http://www.valueram.com/config/type_parts.asp?type=rimm

Thanks for the link... I have one question though, what is the 4-device,
8-device option for the memory? Like I said in my original post, I have
never used or dealth with RDRAM before...

Thanks again,

 

[Arge]

Hi Tim

I am using Rambus PC-1066 on my system and I am only aware of PC-800 and
PC-600. I am not aware of any PC-400, but that is not saying it was never
available. From my experiences I have found that Rambus is more sensitive
than other memory, and I would strongly suggest that you do not mix it. I
do know that trying to run PC-1066 which is based on a 533 MHz FSB system
gives you problems if you run it on a 400 MHz FSB system. I had problems
when running 1066 when I should have been running 800 to match my system. I
ended up buying a new processor based on the 533 MHz FSB system and haven't
had any problems with it since.

Bob

 

[S.Heenan]

Thanks for the link... I have one question though, what is the
4-device, 8-device option for the memory? Like I said in my
original post, I have never used or dealth with RDRAM before...

Thanks again,

I believe the 4,8, and 16 device refers to the way the RAM chips are
organized on the module. For many computers, the Crucial memory selector is
a great tool to discover which types of RAM will work with a given board. In
the case of RAMBUS, they offer no information, since they never made
it.Samsung makes RAMBUS and if you can find a local reseller Im sure they'll
be able to help. You will need a pair of modules, or one RIMM and one CRIMM,
which is a dummy module.
http://www.samsung.com/Products/Semiconductor/common/product_list.jsp?family_cd=DRM040201

 

[Arge]

Hi S. Heenan

Actually you must match Rambus chips. One bank must have to identical RIMM
chips and the other module(s) must have either matched sets of RIMMS or
CRIMMS. Every Rambus memory slot must have something in it. If not memory,
than CRIMMS and they must be in "pairs"

Bob

 

[S.Heenan]

Hi S. Heenan

Actually you must match Rambus chips. One bank must have to
identical RIMM chips and the other module(s) must have either matched
sets of RIMMS or CRIMMS. Every Rambus memory slot must have
something in it. If not memory, than CRIMMS and they must be in
"pairs"

Thank you Arge. It's been a while since I've seen a board using RAMBUS. I
wasnt certain if CRIMMs were needed in all empty slots or just a single
CRIMM to be paired with a single RIMM.