I would forget about the FX-8150 right now, it might have alot of cores but despite that it performs outright horrible compared to similar priced Intel processors.
CLOD does use multiple cores btw, even if it's not to their full capacity.
Just compare the gaming (and other) scores in this,or any other, test with a FX-8150 and a I5 3570K :
http://www.bit-tech.net/hardware/cpu...k-cpu-review/6
A good motherboard for a 3570K would be something based on the intel Z77 chipset.
Personally I like Asus, but others are fine too. Depending on the features you want and overclocking you plan on anything from a ASUS Maximus V Gene down to a ASUS P8Z77-V LX will do.
Compared to your planned Gigabyte it will give you PCI-E 3.0, allowing for a graphics upgrade further down the road without bottlenecking it.
Throw in a good CPU-cooler and those I5's easily hit 4.5GHZ.
A single 6970 like you have now is also enough to run CLOD at pretty high settings at a resolution of 1920x1200 and will do even better at lower resolutions. Add in some quircks and bugs with Crossfire and CLOD, and you are probably better off saving money.
Can always use it to get a new generation graphics card in 2013 or spend it right now on a SSD harddrive, which will help windows and CLOD load faster and give you a more responsive PC in general. Samsung 830 series are really good for their money and a 128GB one will do if it's just for the OS and games (and you don't have tons of games you want to have installed all at once).
Most people who installed a SSD say it's the best upgrade they ever did, and once you've used a SSD system pretty much any regular HDD system will feel sluggish in comparison.
Finally, be sure to compare prices rigorously as some shops are alot more expensive than others.
http://skinflint.co.uk/?m=1 Should give you an idea about prices...just remember to also pick a shop with good RMA (hopefully a fellow Brit can help you here).
Building the thing yourself could also save you some money which would be better spent on beer or slightly better parts. If you've ever built a Meccano kit and can follow a step by step manual it's a cakewalk really.
First time will be a bit stressfull, but just follow the motherboard manual's steps and not much can go wrong.
Oh and have you the deleted Logo.wmv file in your install? It buggers up most ATI cards and stops them from clocking up to 3D speeds..with luck it might allow you to get 30FPS on your current system. So be sure to check this aswell and remember to do it on your new system too.
It just removes the Ubi logo at startup, so don't worry about it messing anything else up.
In your Steam folder, go to "SteamApps\common\il-2 sturmovik cliffs of dover\parts\core\GUI". Rename "Logo.wmv" to any random name (or outright delete it).
Hope this helps a bit and you end up a happy CLOD pilot
and kinda praying you didn't order that FX-8150 allready.. ;(