My son has a computer with a GTX480. He is pretty good about Snoozing Boinc only when he needs to play his games.

I have been thinking about adding another video card.

Power Supply/MB can handle 2 GTX480.

Presently, I have 1 GTX480.

Due to the GTX5xx series, I am expecting the GTX470 and GTX480 to be discounted soon. (if I can find them)

Does it make sense to buy a GTX470 or GTX480... or perhaps, to look for a GTX570 as a 2nd card?

(a coworker suggested that I should sell the GTX480, and buy 2 GTX470 just so the 2 are the same.)

Ideas?

My experiences with mixing different speed cards is that they will always default to the lower speed card. That & you have a hard time adjusting them with something like MSI Afterburner as it doesn't want to read different speed cards right that are paired together.Personally I would go with the same type card ... .Steve

I agree. It would be a good idea to sell your GTX480 now, this week, before the GTX570 comes out; as it is a better card. In terms of value for money the GTX470 is the best card around by some distance, and two would provide good balance. Obviously if you wait for a week to buy a card you could get two GTX570's but they would cost between £600 and £700, whereas two GTX470's would cost £360. The GTX570 would be about 29% faster for crunching, but at almost twice the price. If you sell your GTX480 you might only have to add another £100 to get two GTX470's.
I would not even consider getting another GTX480 - they are too expensive, not worth the extra money.

The GTX580 costs around 380 euro + vat. I guess that the GTX570 is the best value for price.

gdf

I agree. It would be a good idea to sell your GTX480 now, this week, before the GTX570 comes out; as it is a better card. In terms of value for money the GTX470 is the best card around by some distance, and two would provide good balance. Obviously if you wait for a week to buy a card you could get two GTX570's but they would cost between £600 and £700, whereas two GTX470's would cost £360. The GTX570 would be about 29% faster for crunching, but at almost twice the price. If you sell your GTX480 you might only have to add another £100 to get two GTX470's.
I would not even consider getting another GTX480 - they are too expensive, not worth the extra money.

here locally...

Best Buy (www.bestbuy.com)
asus gtx480 - $391
asus gtx470 - $238

frys.com
galaxy gtx480 - $440
evga gtx480 - $400

galaxy gtx470 - $219
evga gtx470 - $240
evga gtx470 sc - $280

i remember about 6months ago that the evga gtx470 was alot closer in price to the evga gtx480.