2006 Dimension 4500 memory question refreshment?

Boy, I hope I'm where I was last week.........just checked, sorry, I am!

I was referred as to some GSKILL memory upgrade kit, and the link given ( the memory ) showed one that has a smooth look (red with a kinda coca-cola logo). Now I'm on the site to buy, but I have a question: This memory shows timing of  2.5-3-3-6, it is DDR PC3200, and right below it is one that is the same, other than it's $10 cheaper (OK for my ol' broke self!), and has the conventional appearance I last saw around 3 years back. It has a timing of 3-4-4-8.

I am, of course, trying to "skate" and see if my XP Pro SP3 will recognize 2GB even thought the machine's maker (Dell) says 1GB is the limit.

I have a webserver running Linux that will take the memory if I can't use it all..............

I realize I could maybe Google this, but since last week's advice came from here, I thought I should ask here.

Regards to all, tarzy