iMac ram in pairs?

I read this on Macworld.com

I wanted to find a pair of 1GB sticks, as Apple recommends adding RAM in pairs for maximum speed.

Click to expand...

Im going to be purchasing a new iMac, and I was going to add a 1 gig stick it. The iMac has a 512 stick in it...will there be much speed loss since the two sticks are different sizes?

The iMacs use a RAM system more like laptops where you don't need to add memory in pairs. You only need pairs for the PowerMacs.

--Cheers

The new Intel based iMacs are laptops inside (ICH7-M chipsets, same as the MacBook Pro), and thus use the more expensive SODIMM chips. These do not need to be installed in pairs, however the Intel Napa motherboard does support dual channel mode, if the RAM pairs match.

So, it's not required, but it will technically speed things up a tad.

ok. a buddy of mine has a rev a G5 iMac with 2 256 dimms. i have an extra 512 dimm. Do ya think its better for him ta keep the 2 256 , or put in the 512 and a 256? Any opinion?