4gb ddr3 dual channel vs (4gb ddr3 dual channel + 4gb ddr3 single channel)

[carboncallate]

Hello people from toms hardware, I want to thank you beforehand because I know u will help me.

I have this situation:

my cpu is a corei7 860
currently I am using 2x2gb ddr3 1600mhz cas 7 (gskill ripjaws) in dual channel mode

I just got 1x4gb of kingston hyperx blu 1600mhz cas 9, but is a single stick.

my questions are:

1) if i put the extra 4gb will i need to put all cas to 9?
2) if i put the extra 4gb will it al become single channel? or the 2x2gb that i already have will continue working as dual channel and only the extre and new 4gb will be single channel?
3) in any case, whats better? to keep the 2x2gb cas7 or to upgrade to 8gb even if that means losing dual channel and getting to cas 9?

ty again

 

[rolli59]

1 yes
2 if different channel people have managed to run dual with 2+2 against 4, this is of course depending you can get them to work in the first place.
3 if you are on 64 bit OS the 8GB what ever channel is better.

 

[scout_03]

that will run in single channel and using 2 kind of memory that they dont have the same cas you could run for trouble and issue the best would be for you to get another set of those ripjaws with the same specs or get another hyperx to match the one you have and sell the one you dont use . so everything will run in dual channel .

 

[carboncallate]

1 yes
2 if different channel people have managed to run dual with 2+2 against 4, this is of course depending you can get them to work in the first place.
3 if you are on 64 bit OS the 8GB what ever channel is better.

ty very much for ur answers

i have another question, if i may ask

yes, i am on 64bit os, so 8gb single channel > 4gb dual channel for os, but that also is true for games?
single vs dual what affects? performance? or load time? or both?

ty

 

[rolli59]

4GB and you can max your ram in gaming, 8GB and you have plenty and it will prevent it from loosing performance as it has to go to the page file with 4GB.
In most applications there is small (measurable not noticeable) performance difference between dual and single channel. http://en.wikipedia.org/wiki/Multi-channel_memory_architecture