Replace Video Card Imac Intel

buy first iMac, need advice on memory and video card upgrade?

I am looking to buy my first iMac computer. LCD 24 " 2.8GHz Intel Core 2 Duo, 2GB memory, 320GB HD and ATI Radeon HD 2600 PRO video card of 256 MB. My first question is, looking at the specifications, said expandable to 4 GB SO-DIMM, 800MHz DDR2 SDRAM. Are iMAC 2 slots of 2 GB each for a total of 4GB of RAM and has 4 slots of 1 GB each for a total of 4GB of RAM? Also manufacturer of memory what would be a good choice? My other question is, I like to replace the video card. A EVGA NVIDIA GeForce 8600GTS 512MB DDR3 graphics card is a good choice or a nVidia GeForce 8800 GS 512MB GDDR3 video card. And every one that fits well? What is also a good anti-virus software that is available to iMac.?

2 slots. It comes with 1 GB each, so you need two sticks of 2GB to bump to 4 GB. Do not Buy Apple. RAM is RAM. There is no "Mac" RAM. I usually recommend crucial to its security, but to buy corsair value select and it is cheap and has always treated me well. Historically, video cards Mac are incompatible with those cards meant for windows. I do not think anything has changed. Certainly not possess the ability to upgrade. ClamXav antivirus software will good when it finally has a use. Stay away from Norton and will be ready. At the moment there are no viruses for OS X. Do not let anyone try to say otherwise. A test some of the Trojans concept, but it's best to just be smart and not enter their password to anything you do not trust. Here, AV is a waste total time would be better spent running regular backups in case of hard drive failure.

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