RAM IN PAIRS need help!

[Muhammet Topcu]

Hello guys, So ive found 4GB of ram in my old pc (DDR3) (2X2GB). I have 8GB in my gaming pc currently (2X4GB). Is it possible if I use all of them like 4GB-2GB-4GB-2GB , TOTAL 12GB.
Will my MB still use dual channel function, or is it compatible, or will it give Errors or BSOD's.
I really want to know this because, Why not 12GB . Thanks!

 

[dark_lord69]

"Is it possible"
yes

"Will my MB still use dual channel function"
I don't think so but only one way to find out!!
Plug em' in and see if the motherboard uses dual channel mode.

 

[yyk71200]

You could try, but it by no means is guaranteed to work. At worst you won't boot. You may have to roll to the lowest common denominator, and test your memory with memtest.

 

[emdea22]

When buying RAM anything other than dual channel kits officially supported is a bit of a gamble. I built countless systems with crazy memory configuration like

4 different dimms of different sizes and speeds NOT on mobo support list - no problems
2 dimms as a dual channel kit same speed latency etc NOT on mobo support list - worked on one mobo / didn't on another (unable to set correct tRFC)
lots of weird combinations even on locked OEM boards that worked

Bottom line: Most of the time it works and since the ram is cheap these days i would just get whatever i can get my hands on. I rarely had problems with ram compatibility - If you want to be sure just get RAM thats listed in your motherboard memory compatibility list.

edit: Dual channel only works if: 2/4 ram modules are installed
Triple channel only works if: 3/6 ram modules are installed
Single channel when 1/3(on dual channel boards)/5(on triple/dual channel boards) are installed

 

[Muhammet Topcu]

When buying RAM anything other than dual channel kits officially supported is a bit of a gamble. I built countless systems with crazy memory configuration like

4 different dimms of different sizes and speeds NOT on mobo support list - no problems
2 dimms as a dual channel kit same speed latency etc NOT on mobo support list - worked on one mobo / didn't on another (unable to set correct tRFC)
lots of weird combinations even on locked OEM boards that worked

Bottom line: Most of the time it works and since the ram is cheap these days i would just get whatever i can get my hands on. I rarely had problems with ram compatibility - If you want to be sure just get RAM thats listed in your motherboard memory compatibility list.

edit: Dual channel only works if: 2/4 ram modules are installed
Triple channel only works if: 3/6 ram modules are installed
Single channel when 1/3(on dual channel boards)/5(on triple/dual channel boards) are installed

And after using all of the ram 12GB 2x2GB 2x4GB, How can I check if my MB is using the Dual Channel Function, And how can I see its not making problems, Will the MB make Beep Sounds On Startup if anything goes wrong?

 

[emdea22]

If PC doesn't start -> problems
-reset bios - still doesn't start -> problems
-gradually insert memory modules one by one - still doesn't start -> problems
At this point i would manually try to find correct timings (including advanced ones) and pre-apply them before inserting all memory modules. This has worked for me in the past but it means you've got to have a decent understanding of memory timings

If PC starts but you can't get into windows -> problems
Same as the above apply

If pc starts and you can get into windows run CPU-Z -> Memory tab should be reporting if its running in dual or single channel mode
Run prime95 blend test for 8 hours -> no errors? -> no problems )

 

[Tradesman1]

What mobo and CPU? If relatively current - and THEY PLAY nice, then yes they should run in dual channel in the config you listed (4-2-4-2 from CPU, and that would be the optimal to try)

And as a FYI, most all newer mobos can basically run dual with 3 sticks contrary to the above (Intel has had flex mode for years and AMD has their own version - under Flex you could say run 3x4GB in slots 1-2-3 and have 8GB in dual and the odd 4 would run in single channel mode - or say an 8GB stick in slot 1 and 4GB sticks in slots 3-4 (8GB in each channel total) all would run in dual channel mode

Big thing is if the mixed sticks will play nice.

 

[emdea22]

@Tradesman1 can you give an example of a platform that does this? I've tested a lot of 775/am2/am2+/am3 motherboards and i've never seen dual channel work in odd memory configurations. For the newer platforms i always used 2 or 4 modules so i have no way to tell.

 

[Tradesman1]

1366 allowed for single, dual or Tri), 1156, 1155 (P67/Z68/Z77), 1150 (Z87/Z97), all 2011 mobos (including v3) can run single, dual, tri or quad in addition to tru Flex), 1151 socket, AMD is more picky as manufacturers have used AMDs version on some and not others (it's not as straight up as Intels Flex mode, as AMD CPU are more optimized towards two stick loads, and AMD 's MC are weaker.

Again the big thing is if the sticks will play nice, it's sort of a crapshoot, and as you mentioned, mixed sticks might play on one mobo and not on another (sometimes even with two identical mobos