Well for games alone an 030 card should be enough, with say anywhere from 8 to 32 megs of RAM (depends on how recent of games) Most games that use 060s will run slow due to AGA anyhow, since they usually are newer 3D ports and such (stuff you can almost always find on PC). 060 does let you do nifty things like play MP3s with it though. I use Visprefs to make 3.1 lok a bit more spiffy, NewIcons is a great icon set, and is only 32 colors. You can download all sorts of datatypes (aminet again) for image and audio files and video, even PDF or HTML, but I use standalone apps for that (AmiPDF and Next work fine usually). AWeb is the best free web browser(unless someone is gonna argue for AMosaic), but Voyager and IBrowse are much better (shareware though). WHDLoad is something you'll definitely want, since it allows you to copy the games to harddisk, and often compensates if you have the wrong ROM for a game. I'm not sure how hi-res AGA can go, but if you want to use a VGA monitor, you'll need a proper scandoubler (otherwise none of the games will work) Amiga specific ones (read: proper hi quality RGB out) cost about 100+USD, generic gaming console ones for the composite RCA jacks cost more like 60USD, depends on how clear of a picture you need.
You can't get gfx cards for the 1200 without spending a lot of money, either on a PCI bus board, or a blizzardPPC + Vision card combo. If you're just doing this for retro gaming and a bit of retro computing, don't bother really, only new games and new apps use that stuff, now, if you wanted to use the Amiga as a serious machine

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