The Use of RDRam

[peyton94]

I have put together a 2.4ghz P4 but the mb requires RDRam. Does RDRam require use in sets of 2? I have 4 slots and 3 sticks of memory. Plus 2 of the sticks of RDRam is 600 not 800 while the 3rd stick is 800 on the speed. Can you intermix the speeds? Next question is can you mix the amount of memory i.e. a 64 stick with a 128 stick?
Curious little ah heck ain't I.
Thanks ahead of time for any help you can give me on this.

peyton

 

[Trashman]

Rdram, must be installed in pairs, either you'll have to buy 1 more stick of 800 or just use the 2x600 sticks and 2 crimms, if ya don't have crimms and you don't want to buy more memory, then you'll be screwed....you can mix speeds, but your problem is havin odd number of sticks....follow?
all memory slots on motherboard must be populated, thats what crimms are for, if you only have 2 sticks, then other 2 slots will be for crimms, crimms are like dummy sticks, just there for continuity.

 

[Lord Evermore]

Technically it's only required in pairs if the controller is dual-channel-only, which all but the first Intel RDRAM chipset are.

Each pair of memory must be the same size in an Intel board (so two 64's and two 128's will work, with each size matched), and all four slots will run at the speed of the slowest module.

If your P4 uses a 400MHz bus, then 800MHz RDRAM is the perfect match for it. 600MHz RDRAM will simply not provide enough speed to keep the P4 fed (600MHz was created so that the less capable chips of VERY expensive RDRAM didn't have to be thrown out; it was only used with the original i820 systems with P3 chips). If you have a 533MHz bus P4, then 1066 RDRAM is what you'd want to install (if the mainboard supports that speed). The P4 does see serious performance differences when you use slower memory. You're better off having a smaller amount of memory if you can match the speeds, than having a huge amount of slower memory, in most cases. It doesn't hurt to test how it works with your system though. Set the system up using only 2 modules of 800MHz, test it out, then try it with the 600MHz modules as well so that the amount of memory is higher but the speed is slower.