Quick question: Upgrading memory

[cpgoose]

Hiya,

My dad has a Dell Dimension 4600 (~3GHz and 256 megs of RAM). We want to upgrade the RAM. There are currently 4 slots on the motherboard, two of which are taken up with two 128mb chips. The book says to only install new RAM in pairs. I saw that Circuit City had 512mb on sale, but it was only 1 chip. The guy in the store said it was fine (since it wasn't in a pair), but I was curious what everyone here thought. Will there be a decrease in performance if we do this?

THanks!

[kschang]

The RAM installed in pairs enables the "dual-bank" mode. There is a small gain if you can get it enabled. However, your PC accepts DDR SDRAM, and the gain you'll get from an extra 512 MB DIMM of DDR SDRAM will far outweigh any loss of performance by losing the dual-bank mode.

[cpgoose]

Cool, thanks for the reply.

Is the dual-bank mode something that you have to enable, or is it just automatically enabled when you install two chips?

[budz]

Cool, thanks for the reply.

Is the dual-bank mode something that you have to enable, or is it just automatically enabled when you install two chips?

Your motherboard has to have the dual channel support in order for it to work.

[HillJack]

Cool, thanks for the reply.

Is the dual-bank mode something that you have to enable, or is it just automatically enabled when you install two chips?

Your motherboard has to have the dual channel support in order for it to work.

That, and if it's anything like me Gigabyte mobo's, you need to install identical (in terms of size, brand, maybe model, depending on the mobo, definitely FSB-speed/timing) chips in specific slots... check your manual/manufacturer's website...

If your mobo has 4 slots, chances are that Dual-Channel will be enabled if you install identical modules in slots 0 and 2; personally, I would throw the two 128's you have now in the garbage and get two (or more) 512's.