[Solved] 8800GT - Upgrade or SLI?

I'm looking for some advice on upgrading my graphics hardware. I’m currently running a single EVGA 8800GT Superclocked, and would like to upgrade for $150 or less ($200, if it’s an amazing upgrade). As I see it, the three best options are…
1) buy a 2nd 8800gt and SLI them
2) buy a newer card and use the 8800gt for Physx
3) sell the 8800gt and add that money to my budget (probably $70 - $100).

Option 1 was always my plan, but it’s been so long since building my rig that I’m not sure it’s the best option anymore. Option 1 is probably the cheapest, although I’ve been using the card for 2.5 years now, so who knows how much life it has left. Options 2 and 3 are much more “future-proof” if I decide to SLI the new card later. Option 2 could be underwhelming b/c of lack of Physx support, and the possibility that the 8800gt isn’t a great Physx card. Option 3 could land me a great card, but is kind of a hassle since I’ll be selling my only card and will have to decide on and purchase a new card immediately. Option 3 could also cause a major CPU bottleneck if I go overboard on the GPU.

Here’s my specs:
CPU: Intel Core 2 Duo E8400 @ 3Ghz
MB: EVGA nForce 780i (using on-board sound)
GPU: EVGA 8800GT Superclocked
RAM: 4GB Corsair XMS2 DDR2
PSU: Antec Truepower Q 850W
HD 1: 150GB WD Raptor (10K RPM)
HD 2: 1.5TB Seagate (7200 RPM)
OS: Windows 7 64-bit
Max Res: 1920x1200

Nothing has ever been overclocked, but I’m considering it. I mostly play single-player FPS and Action/RPG. Recent titles include Splinter Cell: Conviction, Mass Effect 2, Dragon Age, Cryostasis, Oblivion, Fallout 3, Crysis + Warhead, and Far Cry 2. Of course, I’d like to be able to keep playing these kinds of games as they come out in the future, as long as the rest of my system holds up.

I’d appreciate any advice. Thanks, and sorry for the long post!

+1^
I would only go with another 8800GT if its cheap,otherwise go with a GTX 460.

+1

Great, thanks for the advise. It looks like the lowest price on the 1GB version is $240, so that's definately pushing my budget. On the other hand, I could probably do it if I sell my 8800GT. Is it even worth keeping as a Physx card? Thanks again.

Best answer selected by wiekey.