Hi,
I also have an alienware PC.
Mine's an Aurora Torchbearer desktop, with an AMD Phenom II X4 925, 4GB of RAM, and one Radeon HD 4870 X2, which I bought about a year and a half ago.
Join the club! This computer has given me nothing but trouble since I got it. I had to send it back to Florida for repairs
twice! Plus I had to buy Win7 from alienware for an extortionary price just to keep my warranty.
But never mind that.
If you bought your alien 6-8 months ago, then don't even bother trying to return it. Believe me, I've tried. They don't accept returns after 30 (or maybe it's 90, I don't remember) days.
But just try to be patient, hopefully the patch that's supposed to come out this week will fix some stuff.
As to the flickering, I was experiencing that too. Renaming the .exe file worked for me, also you can try this app for tweaking the setting of C2: http://www.wasdie.blogspot.com/
And lastly, today ATI released a driver update (at least for the 4870) that sometimes gets rid of the flickering. I recommend installing the update first and if that doesn't completely help try the app.
Hope it helps, (my main problem is that I can't login to the multiplayer with my gamesas account, hoping the patch will fix that

)
4Strings