can I mix DDR500 with DDR400?

[DUSNOETOS]

as title states.

could I get away with mixing DDR500 with DDR400 memory?

If this would be acceptable how would I go about configuring them to run at the same speed - while keeping a stable overclock.
(i have mixed DDR 400 with DDR333 before and the DDR simply ran at DDR 333 speed - but that system was not overclocked)

I ask since DDR500 seems very hard to find (and very expensive when I do find some) I know that several people have offered some Gskill DDR500 just like my own - but no one has answered my inquiry about them.:mad:

[Rich'[ard]]

i guess you could. the mobo would run the ram at the speed of the slowest kit - ddr400 in your case.

you could either try and overclock the ddr400 kit to ddr500, or downclock the ddr500 to ddr400... i think the latter will be more problematic if your ddr400 doesn't overclock.
make sure both kits can run at w/e voltage you're using as well :thup:

[Bobnova]

Underclocking 500 to 400 is easy, it'll work fine. OCing 400 to 500 is less likely to work.

[DUSNOETOS]

Underclocking 500 to 400 is easy, it'll work fine. OCing 400 to 500 is less likely to work.

That was what I thought....

[SuperMiguel]

can you yes.. want you? why?

[Reefa_Madness]

I don't think that the ram's rated speed is what should be of concern here.

The underlying issue would appear to me to be whether or not the chips in each set of modules are either (best case) identical or at the very least, similar in specs. For example, chips with Winbond BH-5 and timings of 2-2-2-6 would be difficult to run, even at DDR400 speeds, with ram containing Samsung UCCC chips (which I believe is what your G.Skills use), which run at 3-3-3-8 if I remember correctly. The reason being that BH-5 (a DDR400 part), doesn't like running CAS 3, only CAS 2 or CAS 2.5 and if the UCCC (a DDR500 part) doesn't run CAS 2.5, then those two will most likely not be compatible in the same rig. I stated an "if" about running CAS 2.5 on the G.Skills because I honestly don't remember whether or not they will run at less than CAS 3.

Infineon BE-5, a DDR400 part which can be found in 1GB sticks, might however be close enough to work with your G.Skills at DDR400 to DDR430 clocks.

Again, best option is to match the module's ICs, then you aren't likely to have to concern yourself with the rated speed of either set of sticks.

[jaymz9350]

I don't think that the ram's rated speed is what should be of concern here.

The underlying issue would appear to me to be whether or not the chips in each set of modules are either (best case) identical or at the very least, similar in specs. For example, chips with Winbond BH-5 and timings of 2-2-2-6 would be difficult to run, even at DDR400 speeds, with ram containing Samsung UCCC chips (which I believe is what your G.Skills use), which run at 3-3-3-8 if I remember correctly. The reason being that BH-5 (a DDR400 part), doesn't like running CAS 3, only CAS 2 or CAS 2.5 and if the UCCC (a DDR500 part) doesn't run CAS 2.5, then those two will most likely not be compatible in the same rig. I stated an "if" about running CAS 2.5 on the G.Skills because I honestly don't remember whether or not they will run at less than CAS 3.

Infineon BE-5, a DDR400 part which can be found in 1GB sticks, might however be close enough to work with your G.Skills at DDR400 to DDR430 clocks.

Again, best option is to match the module's ICs, then you aren't likely to have to concern yourself with the rated speed of either set of sticks.

I'm pretty sure the gskills are rated for cas 2.5 at ddr400, not 100% but thats what I remember the jedec specs on mine being.

[DUSNOETOS]

Here is a screen shot of what Cpu-z says:
75948