Audio
This is the exact card I put in a customer's machine last week and it sounded REALLY good hooked up on the store's surround.
http://www.newegg.com/Product/Produc...82E16829117108
I mean for the price, it's a great deal, I highly recommend it.
Video
For video, stay away from ATI. It's that simple. NVIDIA whoops their ass every year in card comparison in performance and price. (Kinda like the match between AMD and Intel). I would
recommend going with a PCI express card, reason? They Nvidia and ATI are currently working on their last AGP cards and have both announced that they are going to transition completely to PCI X. (PCI express will quickly take AGP's place, so people without PCI express boards are shit out of luck until they get a new board). Which is another perdicament you are in, your 300 dollar machine probably doesn't have a PCI express slot, and you don't want to run a 16x card at 1x (waste of $ + time).
But, here's the card i'd recommend. (guessing everythign is compatible)
http://www.newegg.com/Product/Produc...82E16814140051
It's the card I had in my old machine 256meg NVIDIA card produced by Apollo, model = FX5500. I mean you get better FPS than you probably have now by a longshot, it's only 75 dollars, so you are getting a good deal and it's 4x/8x (your board probably 4x so it will work nicely
).
Other than that, if your only using it for Diablo2 and Porn you don't need much more. This will be plenty, hell, if you have a decent enough processor and about 512 ram you can play Battlefield: 2 demo and eventually the retail version. (FX5500 the cut for the game).
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