Needs help upgrading RDRAM!

[Massey1Bravo]

Hello guys,

I know this is a rather stupid question to ask, but I need help upgrading RDRAM....

I currently have a Asus P4T Motherboard on Intel 850 chipset, (Socket 423 P4 1.5Ghz) with 2x64mb PC800 Rambus RAM. I have 4 RIMM sockets with 2 populated with RDRAM (RIMMB2/RIMMA2) and the other 2 populated with C-RIMMs. (RIMMB1/RIMMA1)

I've recently purchased a 256mb RDRAM and replaced one of the 64mb RDRAM. after that when I started the system I started hearing BIOS beeps. (Which indicated that there are no DRAM detected)

Now I'm planning to buy another 256mb RDRAM, and I really want to know if it'll really work before I spend hundreds of dollars on it. :confused:

[mainfrog2]

You will need to make sure that your memory is installed with the largest in the first slot and then the smaller one in the second slot or it won't recognise the memory modules. Also have a look here for some more help.Memory Installation Tips (http://www.crucial.com/uk/helpdesk/troubleshooting_tips.asp)

[Out Of Trim]

Hi Massey1Bravo -- A quite diffucult question..

It is my understanding that ony one type or RAM Memory dimm can be used in the same system. In other words, you should match the original type of RAM as supplied with your original system.

This link has plenty of helpful guidance and support available:-

http://www.crucial.com/uk/store/listparts.asp?Mfr%2BProductline=Asus%2B+Motherboards&mfr=Asus&cat=RAM&model=P4T&submit=Go

However it would appear that the particular Memory that your Motherboard uses is not that popular and therefore not well supported. However, perhaps if you contact Crucial they will be able to guide you further.

Good Luck!;)

[Massey1Bravo]

Thanks for the comment people, let's hope that 2 256mb's will work.

Oh, one more thing. If you keep the two 64mb’s installed and add two 256mb’s and you are using Windows ME or 98 you will have to adjust the VCACHE.

Is it actually possible to have both the 2 64mb's and the 2 256mb's together? I've never seen a PC with 640mb of RAM.

[ORAC]

Remember, when nothing else works, as a last resort - RTFM!!.

P4T manual, pages 22 & 23 (amended from 128Mb to 256Mb):

1. The memory configuration of channel A (RIMMA1 and RIMMA2) and channel B (RIMMB1 and RIMMB2) must be identical, (see below).

2. C-RIMMS (Continuity RIMM) must be used to complete the sockets that are not populated by RDRAMs. A C-RIMM is necessary to avoid breaking the signal lines, which make serial connection in a Rambus interface, such as used in this motherboard. This ensures the electrical integrity of a Rambus interface.

3. When C-RIMM are required, it is recommended that they be inserted into RIMMA2 and RIMMB2.

Total system memory is 2Gb max.

Examples. (Note: When using only two memory modules, it is recommended use use configuration (a).)

(a).
RIMMB1--------256Mb RDRAM
RIMMB2--------C-RIMM

RIMMA1--------256Mb RDRAM
RIMMA2--------C-RIMM

(b).
RIMMB1--------C-RIMM
RIMMB2--------256Mb RDRAM

RIMMA1--------C-RIMM
RIMMA2-------- 256Mb RDRAM

(c).
RIMMB1--------256Mb RDRAM
RIMMB2--------256Mb RDRAM

RIMMA1--------256Mb RDRAM
RIMMA2--------256Mb RDRAM

Working on the above, what you have, and what you're buying, you should install as follows:

(c).
RIMMB1--------256Mb RDRAM
RIMMB2--------64Mb RDRAM

RIMMA1--------256Mb RDRAM
RIMMA2--------64Mb RDRAM

:cool: :D

[Massey1Bravo]

ORAC:

I DID read the manual, but I interpreted that "The memory configuration of channel A and Channel B must be identical" was about the C-RIMM and RDRAM configuration because they did not mention anything about the size of the RDRAMs. When I hear the BIOS beep codes I started to worry. (And that's why I asked the question)

TCS:

I'm using WinXP Pro.

[CrashDive]

Not sure if it helps in this specific instance but here's a site I buy RAM of all sorts from: http://www.crucial.com

The UK specific one is: http://www.crucial.com/uk/index.asp

Nb. They do other countries too, see the drop down-combo box in the top left of their pages.

I've always found them offering good prices, very prompt delivery and, perhaps more importantly, the correct memory for the job / machine.

Ps. I'm not associated or affiliated with them in any way - just trying to pass on a hopefully useful link.