I could be wrong, but it may be possible that Dell RAM is proprietary, meaning you may need to buy it from Dell which could get expensive.
Nah, I had a straight-up Dell, and had no problems updating the RAM. Of course, that was back when it was PC133 RAM... *cough* The only thing that's really a problem with Dell stuff is that when I rebuilt it (better, stronger, faster!), the hard drive decided it didn't want to be a slave drive, it
had to be the primary. Period. Otherwise it didn't even show up on the new mobo.
But yeah, the website ought to have it, or you can call Dell and ask the tech-support. I know it's gone seriously downhill in the last few years, but that's a simple enough question that they ought to be able to handle it.