Dual Channel in mixed pairs?

[LIVAN]

Ok guys, thanks in advance but I really need help here.


would like to upgrade my current Dell 9150 Pentium D 3.2ghz , 2gb to 3 GB. I now have 2 1GB sticks running in dual channel. I know I can stay in dual channel even with 1gb+512mb(channel 1) and 1gb+512mb(channel 2) but my question is, do the 512mb sticks have to be the same specs(ie ram chips, brand) as the 2 1GB sticks?

Or am I even correct I can still run dual channel like this?

What if I go 4gb, 2 pairs of identical pc4200 and 2 pc5300?


What if I get 3 1GB sticks , all the same specs? Will that work? Thanks in advance

 

[AstroGuardian]

Since you need lots of ram, there is no point in running them in single channel.
So, you have these options in order to run in dual channel:
1. {(1x1Gb)+1x512} + {(1x1Gb)+1x512} in order to have 3Gb in dual channel 2x512 must be same and 2x1Gb must be the same
2. {(1x1Gb)+1x1Gb PC4200 or PC5300} + {(1x1Gb)+1x1Gb PC4200 or PC5300} in order to have 4Gb in dual channel 2x1Gb PC4200 must be same and 2x1Gb PC5300 must be the same.

I hope this helps. You can run memory in dual channel no matter the brand and type of the memory chips but there is no guarantee that the system will be stable. So the rule is that you should use ONLY identical modules in order to have a healthy dual channel memory set no matter the number of the memory modules.

 

[Roguestar]

Dual channel isn't as strict as you think.

http://en.wikipedia.org/wiki/Dual_channel

Multiples of 2 is generally the way to go, unless your motherboard specifically has features that comepensate otherwise (the P965 has features that allow you to run three sticks and it'll treat two as dual-channel and the last as single).

 

[LIVAN]

Originally posted by: AstroGuardian
Since you need lots of ram, there is no point in running them in single channel.
So, you have these options in order to run in dual channel:
1. {(1x1Gb)+1x512} + {(1x1Gb)+1x512} in order to have 3Gb in dual channel 2x512 must be same and 2x1Gb must be the same
2. {(1x1Gb)+1x1Gb PC4200 or PC5300} + {(1x1Gb)+1x1Gb PC4200 or PC5300} in order to have 4Gb in dual channel 2x1Gb PC4200 must be same and 2x1Gb PC5300 must be the same.

I hope this helps. You can run memory in dual channel no matter the brand and type of the memory chips but there is no guarantee that the system will be stable. So the rule is that you should use ONLY identical modules in order to have a healthy dual channel memory set no matter the number of the memory modules.

Yes that helps tremendously, thanks! I was thinking along those lines but I just needed confirmation! Thank you!