Can i install 1 pair of 1g memory along with 1 pair of 2 gig memory?

ccgraf

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I have a MSI MB with 4 memory slots allowing a total of 8 gig of memory. I now have 2 1 gig sticks of dual channel DDR2 1066 memory installed. Can I install 2 sticks of 2 gig DDR2 dual channel 1066 memory in the 2 ramaining slots to give me 6 gigs of memory? I have searched the MSI site but couldn't find the answer and the manual doesn't specify either. I want to bring memory up to at least 4 gigs so I can upgrade from XP to WIN7.

Thanks for any help

Jim D
 
Solution


If their identical across both channels they should. He's saying 2 x 1Gb + 2 x 2Gb sticks, this is possible if installed in the following configuration.
(Assuming channel A and channel B, some boards switch the reference up, please read your manual).

DIMM_A1 => 2GB
DIMM_B1 => 2GB
DIMM_A2 => 1GB
DIMM_B2 => 1GB

Turns into
Channel A => 2 + 1
Channel B => 2 + 1

That can run in unganged mode just fine.
Welcome to Tom's Forum! :)

ANS: Yes and Be Careful. Most Dual Channel MOBOs allow mixing sizes, though not all; see your manual or post you exact MSI MOBO and I can double check. Next, the Be Careful - you want both sets to have the EXACT same CAS Timings and most particularly Voltage.

Therefore, please post the following links:
1. Current MOBO
2. Current RAM
3. Proposed RAM
 

ccgraf

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Thanks for the response Jaquith,

The MB is a MSI K9A2 Platinum, The manual just states up to 8 gig of memory can be installed but gives no specifics other that to use pairs of matched dual channel. I have 2 matched 1 gig dual channel DDR2 sdram 1066 (PC8500) by Mushkin installed. Plan to install 2 matched 2 gig sticks of the exact same specifications except they are Kingston (Mushkin is no longer making the 1066 DDR2 memory in 2 gig sticks.

Thanks,
Jim
 


If their identical across both channels they should. He's saying 2 x 1Gb + 2 x 2Gb sticks, this is possible if installed in the following configuration.
(Assuming channel A and channel B, some boards switch the reference up, please read your manual).

DIMM_A1 => 2GB
DIMM_B1 => 2GB
DIMM_A2 => 1GB
DIMM_B2 => 1GB

Turns into
Channel A => 2 + 1
Channel B => 2 + 1

That can run in unganged mode just fine.
 
Solution
^If that's the correct Channel layout then I agree.

A > B = 2*B ; A < B = 2*A ; A = B == A + B and there's no loss. The size per Channel for Dual Channel should be equal, otherwise some MOBO's will simply ignore extra RAM e.g. Ch A = 4 & Ch B = 2 {A > B = 2*B} or 4GB.
 

ccgraf

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Thanks for all your help guys :). I've ordered the 2 2gig sticks because I wanted to have at least 4 gigs and the price of the 2 gig strips was within a few bucks of the price of 2 1 gig strips. I also ordered WIN 7 which has 2 disks; 1 for 32 and 1 for 64bit. I'm not sure if all my progs will run on 64 as some are a little old but I'll try 64 first and see. I'll post the results when I get everything installed, hopefully sucessfully. I might try some overclockig too.

Thanks again.
Jim D
 

ccgraf

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Hi,
Just wanted to thank you for your help. I installed WIN 7 yesterday and it immediately recognized the 6 gig of memory. I'll run some speed test comparisons to find out how it ranks.

Thanks Again

Jim D