What is causing my low framerate in Prototype 2?

[Kadyn]

So my computer is pretty good, it can all but max out Max Payne 3, Mass Effect 3 and plenty of other games. But for some reason, even on the lowest settings (1280*800 resolution with everything set to off or low) Prototype 2 still lags a bunch.

Machine Specs:

Twin HD 5770 in crossfire.
Processor is quad core i5
4GB DDR2 Ram (Maybe it is this?)
SSD hard drive (but its running from a 7200rpm hard drive.)

Any ideas on why I am seeing framerate issues?

[gionna]

There are some serious issues with the PC port of Prototype 2, from what I can gather.

Most people who have complained about the game's performance have been running on ATI graphics - I'm not sure that 100% of the people having issues are ATI'ers, but from my sample size of probably 20-30 people, I've found most nVidia graphics users to say "it runs great!" and most ATI graphics users to say "Wow, this stinks!"

I went through and collected and collated all the suggested solutions to the problem over here, on my blog but the #1 thing that actually helped me was setting the processor affinity.

If I use Task Manager to force the processor affinity of prototype2.exe to only core 0, the game runs smoothly without issues. If I don't, then I get all sorts of performance issues - sometimes the input lags, often times the frame rate drops like a rock, etc.

If that doesn't work, you can try some of the things that others suggested and had good luck with, but that's where I'd start.