posted on May, 21 2009 @ 02:51 PM
I've had memory purchased directly from Dell, stating on their website that it's the proper upgrade, end up being incompatible with a particular
... more issues with DDR2 than any other.
Some boards Do require installation in pairs and some even All pairs must be the same (size, speed, etc). Again, mostly in the proprietary package
systems (Dell, HP, etc.).
What is your make/model/system?
[edit: to add]
Most motherboards do have a limit with regards maximum size memory module they will accept/support per slot. If it's an older system, even by a few
years, it may very well Not support 1Gb sticks per. Once again, mostly in the package systems.
[edit on 21-5-2009 by 12m8keall2c]