Strange, I have an intel i7 870 @2.94GHz (quad core), 8GB ddr3 ram at 2000 speed (pr whatever its called) and 2x GTX 460 on sli (the ones with 765mb memory not 1Gb) and also running on 2 monitors. The game is on one monitor but the fact that I have a 2nd one alone always creates a small drop in frames (sometimes unnoticeable) since the cards are configuring graphics for another monitor simultaneously.
With this rig I found Hawken on Closed Beta 1 to work just fine. As you saw I don't have a fuzzy bunny PC but I don't exactly have the latest in cutting edge either, and it is around 1 year old atm. Oh, the HDD I am running the game on is also not that crash hot, it was an older HDD. When I drop the graphic settings I see a significant boost in performance. Also, when running a program like fraps and recording on high settings I get larger frame drops, and lower settings fixes this. In my experience the low settings look good and run very smooth, even on Titan which was by my experience the level with the highest frame drop. It had the most detail. But other than that, without fraps, the game runs great even on full graphics.
Are you sure it isnt something else (other than the games' fault) on your system bringing frames down_
Running simultaneous programs can cause memory drain in cases we don't even pick up sometimes. I run Google chrome for example, and having it open on the 2nd monitor with around 20tabs (as I pretty much always do) creates a larger memory drain (you can see this in task manager too). I still keep it on but if frame drops persist on some games I close it and sometimes even disable the 2nd monitor.
Widgets create a drop in frames too. See if you have any of them open that again drain large amounts of memory without you knowing it.
I used to have 3 to 4 basic widgets always running, until I realised those damn little insignificant (as they seemed) things actually drained more memory than what I expected and believe was needed. I noticed a a 5 to 10 frame gain in games like RAGE. 5 to 10 might not be much, but if the game is running at 25fps 30 to 35 is actually indeed a difference.
Shooters are meant to run at 30fps (sometimes they even cap the frame rate in many shooter games so as not to go over 30fps, in those cases people think their pc's are dropping frames or the game isnt well developed, this isnt true it's just a frame cap.) Racing games and that sort need to run at 60fps. So if your Hawken experience isnt too much under 30fps you don't have a real problem.
Also check if you have the optimum drivers for your gpu. Some beta drivers that auto-update decrease performance due to testing new things out. Sometimes even the proper drivers decrease performance too. Keep that in mind and if you are running Win7 it's a good idea to do performance tests with one driver and then the other. I had updated to a newer driver that dropped my gpu score from 7.9 to 7.5 and I noticed significant frame drops too. I went back to the older driver until an even newer release came out, a month later or more, which fixed this problem.
Lastly, heat. Make sure your PC isnt overheating. If so, you will not see true performance until this is taken care of.
Intel chips also reduce their performance as soon as heat begins to surpass the trajectory max.
On my own pc, I delayed the cooling side of things a couple weeks (I made the whole rig up from scratch by myself so I had the opportunity to leave some small things out to compensate for them at a later time) and for that 1st phase of my PC the intel chips where working at 30% of their actual speed.
The performance drop was dramatic. Even in the Win7 performance score (which as you have probably guessed I use frequently to see if windows is actually seeing and using the hardware properly) from a 7.5 ranking it was at 6.5! I ran other tests too and it was working at just less than a 1/3 of it's actual performance. So cooling is a huge deal.
You might not have as big of a problem as I did (70% performance drop is simply out there) but you might have a 20% drop that you usually don't notice. Even if the cpu runs at 80% of its capacity it makes a difference. You might not have noticed this before because some other games don't push it that much_ Possibly better implemented games as well, but that does not mean Hawken is not well optimised. It just might not be as optimised as other games.
Your hardware from what I guess should run the game pretty much smoothly, especially when you drop the graphics down. So I am guessing something else might be bringing your rig back. Also, I quickly mentioned it before, the HDD you run the game on is also very important and sometimes much more important than other things if it is old. The space on your HDD as well as the rpms and so on. Check to see if this might be the problem with your performance too. Although, I kinda doubt it. Only the really fuzzy bunny or extremely old HDD's drop performance, but when they do, omg, they drop it in the most noticeable way. My secondary HDD from which I run games atm is rated at 5.9, which is pretty fuzzy bunny and old, and yet it is good enough to make the latest games run smooth. So, the HDD creating problems is a long shot but I thought I throw it in there too.
You should by my guesses have a very smooth experience for the hardware you own, especially at low settings. Check to see if something else is wrong with the way things work on your pc and make sure you don't have a large amount of memory wasted on unnecessary programs (either visible or unneeded running services from installed software). And if you do and believe they are necessary, try to be honest with yourself and see if they really are
(I know I had plenty at times that tbh weren't really necessary, lol
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