I'd go with the 460. It has more than twice the raw graphics power, and it will be plenty to drive AutoCAD. Eventually they will create drivers for the 400 series chipset that are certified for AutoCAD. It will do just fine for AutoCAD and make a huge difference in gaming. I'm quite happy with the GTX 460 in my setup.
I think people tend to go overkill when they are looking at cards like the FX1800. Unless you do a lot of rendering, you will not need it. That being said, I would stay away from the GTX cards and go with a cheaper Quadro card. I happen to have an FX1500 because it was a replacement for a defective FX560 (never liked the 560, very happy with the 1500) and I have no problem with 3D or rendering. I know several people who use the Quadro FX580 and love it for both ACAD and Revit and you can grab it off Amazon for less than $150.00. For most people, this card will be more than they ever need and seems to be a great match for ACAD 2011. I would stay away from a gaming card when you can get one that was designed to work with ACAD for the same price.
The poster was asking what card would be the best for both AutoCad and gaming. Also, if you look on the certified graphics hardware list you will see that cards from the GTX series on the list. The latest card on the list is the GTX 295, so they are one generation behind.on the drivers. I think that most people are in agreement that nVidia doesn't tweak the drivers for the gaming cards to be used in AutoCad, so they are effectively crippled, but I think most people are also in agreement that the gaming cards are much more powerful cards for a fraction of the cost. I have owned a Quadro FX 3500 and it didn't perform as well as my 9800 GTX+.
Just my opinion.
Go with the 460. You'll be a lot happier. It'll run Autocad and 3DS Max just fine. Revit isn't even an issue as it doesn't really use the graphics card anyways.
The only thing I've noticed about the 480 vs a Quadro card is that the Quadro card seemed to be more precise when it comes to displaying the CAD info. (it's hard to explain). The Quadro's seem to show each pixel better. For instance, when I zoom completely out, sometimes the text will change to white (just visually). If I zoom in a bit or pan.... it switches back.... which tells me the 480 isn't quite as precise. It's not a big deal, I don't even notice it anymore.
This is so funny. I run a dual core intel processor with a GTS260 with autocad 2011 and that runs just fine.a $70 card vs the $260 you propose and your worried about a $3000 card? I work as an engineer for a living and I see no reason to buy any card that Acad really doesn't need. Look at the System specs for acad2011 I'm pretty sure that 128mb video card will do just fine. I have a 1ghz card costing only $70 will do the trick.
For basic 2D Autocad... sure, your set-up is just fine. I'm actually running Autocad MEP with large Arch and Struct models referenced from various 3D programs. I posted this in the Autocad 2011 forums since there was a larger base of people to reach. You'd be surprised how much Autocad MEP pushes your system.
Right now I'm running an Intel i7 @ 2.8ghz. 6 GB of Ram. Windows 7 64bit. OCZ Vertex Solid State Hard drive. And the Nvidia GTX 480. And I still wish I had more processing power. Probably towards the end of the year I may get another 480 and link them. I'll probably also add another 6 GB of Ram.
I hope I can stop you from wasting some money. http://www.slizone.com/object/slizone2_game.html at the bottom of the page shows programs that can benefit from SLI mode. I do not believe AutoCAD would benefit. My thoughts anyway.
FYI my specs are
Win 7 64
12 gig ram
I use AutoCAD/CadMep+, and Navisworks. I am happy enough with the card for the price. I think the quadros are crazy priced, but they are for a reason. Our cad dept has quadro 1800's and one person has a 3800. Their machines are Xeon workstations though so it is hard to compare them to mine. Lets just say for the price difference I am not that impressed, but if it does go faster we all know time is money.