- What will it cost?
- What sort of improvement to performance can I expect (can I play Shogun 2)?
- Will any power savings pay for some new card?
I compiled some stats from previous years, did some (very) rough math and came up with this worksheet:
GPU decision worksheet. It turns out that my pair of 8800GT offers identical performance to a (more) modern GeForce GTX 460 (1GB RAM), which offers sufficient performance to play Shogun 2.
The upshot of this? I can play Shogun 2 on my current rig, and it's very unlikely that I can recover the cost of the new GPU through power savings. No new kit for me :-(