Ram compatibility question

I'll leave this short and sweet:

Will this computer;

http://support.gateway.com/s/PC/R/1009400/1009400sp2.shtml

Be compatible with this ram;

http://www.newegg.com/Product/Product.aspx?Item=N82E16820145527

And will I notice a difference (going from 1GB to 3GB), mainly on videogames and use of the internet. Seems a good deal.

Yup the ram will work and you have an empty PCIe x16 slot, so you can upgrade your GPU with something decent.

I don't see any specs for your PSU, but this card should run on whatever you have.

Much appreciation!

are these simple to install, basically opening the case, adding them to their appropriate slot (without removing old parts) and presto I'm golden? And will I notice a significant increase in speed, FPS, whatnot? Basically I want to upgrade this gateway to run games like Hellgate until I create a gaming PC later this year, so as long as I can get decent settings with the extra ram and cheap card I'm happy.

Installing a GPU is pretty easy. Not as easy as adding ram, but still very easy. I bet there are a lot of gudes out there if you feel uneasy, just google guide to changing video card, or look on youtube for a video.

Going from onboard video to almost any GPU will be a night and day difference. You will wonder how you lived with that onboard.

The 8600GT I linked is by no way a power house card, but for the price it is a very good card.

Nothing wrong with getting 3GB or ram, but you will see more of a jump in performance going from 1 GB to 2GB than 2GB to 3GB.