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What is the difference between memory sticks - 4 chips per side vs. 8 chips per side?
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01-03-2012 01:13 PM

Looking for 2 - 1GB PC2100 (DDR266) or 1GB PC2700 (DDR333) laptop Ram on the internet sites and have noticed there are two different configurations (4 chips per side vs. 8 chips per side) for the same thing but with different brand names. Could I use either type in an R40 to upgrade it, or is one type better than the other? Please pardon the question if it sounds lame, but I am just learning about laptops and really don't know the answer.

Thanks for the help!

Harrison

The 4-chip-per-side is called high-density, the 8-chip is low-density.
With PC2100 and newer/higher, it makes no difference which version you use, both will work equally as good.
If you buy 2 modules, always get 2 of the same.

In the 'olden days' of PC133/PC100/PC66 it was important to use specific density as per laptop requirements, because RAM management wasn't as advanced.
E.g. a T20/T21/T22 needed low-density RAM, but the T23 already handled both low and high.
From T30 onwards, density has become irrelevant, and was mainly due to whatever RAM-chips the module manufacturers had available.

RealBlackStuff,
Thank you for the answer. From it, I gather an IBM R40 could use either one.

Yup.