Can you put DDR3 in any slot on mobo?

mroldboy

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Simple question my HSF covers slot 1 of my mobo, can I use slots 2,3,4 instead with 3x2gb.

The ram I want to get have large heatspreaders

edit: found a few posts elsewhere that indicated you can. Can any one confirm?
 




With that mobo, it would be better to use 2x2GB (slot #2 and #4) and have it run in dual channel mode rather than 3x2GB in single channel. However, if you wanted to run all 3 DIMMs in slots 2, 3, and 4 there should be no issues.



 

gracefully

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If slots 2, 3, and 4 are used with 2GB modules, slots 2 and 4 run in dual channel, slot 3 runs in single channel.
 


You might want to verify that info. There is no mobo and memory controller that I know of that will run DIMMs in both single and dual channel mode at the same time with 3 DIMMs installed as you imply. AFIAK, if 3 DIMMs are used then all memory runs in single channel.
 

gracefully

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It runs in asymmetric mode, L-shaped mode, flex mode, or whatever each manufacturer calls it. Right now, I have 2x2GB. Max RAM read speed is 16GB/s. If I add another 1GB stick I have around (I don't put it in because it's virtually useless for my purposes so far), Max read speed is still 16GB/s, something that single-channel DDR3-1333 CL9 cannot achieve. It drops to 8-9GB/s some time during the benchmark, which leads me to believe that 1GB is not in DC mode.
 


Flex Mode is when you have 2 DIMMs (1-1GB and 1-2GB) populating slots 1 & 3. The first half of the 2GB DIMM operates in dual channel mode with the 1GB DIMM and the other half of the 2GB DIMM operates in single channel mode.

You can run 3 DIMMs in dual channel mode but only when the combined capacity of channel A equals the the capacity of channel B. For example, 3 DIMMs of 1GB, 1GB, and 2GB populating slots 1, 2, and 3, the combined 1GB DIMMS in slots 1 & 2 (channel A) equals the 2GB DIMM populating slot 3 (channel B).

3 DIMMs run in single channel when all DIMMs are of the same capacity.
 
Yes.

However 2x2GB (4GB total RAM) DIMMs would server you better in the long run and/or if using a 64bit OS, unless money is an issue, then 2x1GB DIMMs would be fine; although 2x1GB would be the minimum with a 64bit OS and 2x2GB DIMMs is preferred. For a 32bit OS, 2x1GB DIMMs is fine with no worries.
 

mroldboy

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I am going to stick with my one 2gb stick for now. And jump on the next deal of used sale of a 2gb stick that can run at 1.7v like my current ram.

I just bought the hs 4870 and a 620hx so I need to hold off on another purchase for now.