Memory upgrades

[BillB]

I have company computers that were delivered (in 2006) with 512 MB of RAM. These are low-end computers with 2 memory slots with 256 MB modules of DDR2 in each.

Crucial (http://www.crucial.com/systemscanner/index.aspx - IE only) says

Although the memory can be installed one module at a time, the best performance comes from using matched pairs of modules.

I can buy 1 GB modules for about 5% more per GB than 2 GB. Is it worthwhile to throw away that other 256 MB and have a matched 2 GB rather than an unmatched 2.25 GB? I'm expecting such a performance improvement anyway that I might as well save $40 across the office and upgrade another machine.

[dewey]

The first thing is to check to see if the computer/BIOS will support 1Gb or better chips.  Often the BIOS will not recognize the large chips - a BIOS update will often solve this.

The other problem is the power applied to the memory slots may not be sufficient for the larger chips.  We ran into that problem with some Compaq machines way-back-when. 

Another problem is that some machines require matched memory - you cannot mis-match memory sizes in the slots.  We had that problem with Gateway and early Dells.  Although you can use only one chip, if there are two they MUST be the same.

I doubt the performance increase between 2 x 1Gb, 2Gb +256 Mb and 2Gb (1 chip) will be noticeable if the machine will boot.