Mixing single & double sided DIMMs?

[Justin Baker]

I'm looking to buy a socket 939 board and I want to use my existing RAM if
at all possible - I have four Crucial 512Mb DDR400 DIMMs, two of which are
single sided and the other two are double sided. If I put the single sided
DIMMs on one channel and the double sided DIMMs on the other channel, is
this likely to work?

Thanks,

JB

 

[General Schvantzkoph]

I'm looking to buy a socket 939 board and I want to use my existing RAM if
at all possible - I have four Crucial 512Mb DDR400 DIMMs, two of which are
single sided and the other two are double sided. If I put the single
sided DIMMs on one channel and the double sided DIMMs on the other
channel, is this likely to work?

Thanks,

JB

As long as you pair the single with the single and the double with the
double it will work fine.

 

[Justin Baker]

As long as you pair the single with the single and the double with the
double it will work fine.

Thanks for the reply, I was hoping that would be the answer!

Next question, will I be able to run the memory at DDR400 in this
configuration, or will it fall back to DDR333?

Thanks,

JB

 

[General Schvantzkoph]

Thanks for the reply, I was hoping that would be the answer!

Next question, will I be able to run the memory at DDR400 in this
configuration, or will it fall back to DDR333?

Thanks,

JB

A single sided plus a double sided on each bus will run at DDR400. The
speced speed for a system with four double sided DIMMs is 166MHz (DDR333),
for a system with two double sided and two single sided the speced speed
is 200MHz (DDR400). However if you use faster memory and up the DIMM
voltage slightly a system with four double sided DIMMs can run at DDR400
reliably. I have 4G in my X2 4400+ system. Initially I had two pairs of
OCZ value RAM. With that configuration I was only able to run at 166MHz. I
replaced one pair with OCZ performance RAM and upped the DIMM voltage
slightly and I've been running at 200MHz for months without a single
hiccup.