OK to use 400MHz Rambus with 800MHz Rambus / RIMM?

[Michael Steele_2]

Hi, need some more RAM in my PC. ( don't we all ). Currently have 128 MB of 400MHz RIMM in a MSI motherboard.

Will 800MHz work with 400MHz RIMM?

I'm thinking that all the RAM should be the same. Either all 800MHz or all 400MHz but not a combo of the two.

Also, I currently have 1.5 GHz Pentium 4 CPU. Any compatibility problems between the 1.5 GHZ CPU and the 800MHz RIMM?

[Ronald Postma · Accepted solution]

Hi Michael,
It may work, but it als can cause problems. Depends on the motherboard. If the motherboard itself supports 800Mhz, it will work, but both on 400Mhz. If the motherboard only support 400Mhz, it might work depending how backwords compatibel the 800Mhz module is.

But it is more advisebel to put in a 400Mhz RIMM. If you give me your model of motherboard I may be abel to give you some better advise.

[Michael Steele_2]

Well, you hit it right on the nail. My motherboard has the limitations. MSI 850 Pro limited to 200 MB or 400MHZ RAM. What a downer.