Windows 8.1 is better for gaming for sure. You made the right call.

Nice setup you got there! I myself like Nvidia and Intel more than Amd, but hey, pc gaming is pc gaming at the end of the day, glad you could come back to the dark side >:)

Alright, just making sure you knew where the bottlenecks where, that's a beautiful PC you have, enjoy it :) (btw, you have the same tower as my brother, lol)

The first option for sure, but the other two are very easy.

Look at the cathodes (nothing more than fluorescent tubes). Just look for one of the molex plugs that your PSU has, they look like this

connect the adaptor that powers the cathode(s) and voila! Job done. You'll only need something to hold the cathodes where you want them. Like double-sided adhesive tape.

What can be easier than that?

Just don't put them on the side panel, of course, but maybe at the "ceiling" of your case and/or the back next to the exhaust fan so the light can be visible through the window of the side panel.

Gratz! Have fun and don't play too much Legends of Grimrock ;)

What do u mean, have u seen me play it on Steam?

Still sounds a little complicated. What are you talking about lol?

At the other end of the scale I built my PC back in October I think last year for £230 (already had a 1TB HDD).

AMD A10 5800k
Radeon HD6670 2GB
Motherboard I forget the name of
8GB memory (2x4GB)
cheap case with psu
2 xDVDRW drives

Absolute cheap ass system but works well in dual graphics mode and plays all games well (not always at full detail). Quad core 4ghz processors seem fast enough for me.

Runs 3D games well on my passive 3D tv.

Skyrim screenshot below. 1080p and fast frame rate. Just making the point PC gaming doesn't have to be expensive. My PC costs less than a xbone and ps4 but delivers superior cpu performance and graphics performance between the two consoles. Also more memory and a faster hard drive. I've not been disappointed with the performance of any game although have had to adjust down some detail on later games. I can also do the xbone thing of rendering at a lower resolution and upscaling if necessary. Haven't needed to do this yet though.

Yeah found it pretty cool because I've played it a lot as well.

Because that 10% makes no difference, and anyone who is good with money knows that.  The Titan for example is the definition of the dumbest thing I have ever seen.  When it released it was only 30-40% stronger than the 7970 GHz, and yet cost 3x as much.  On top of that, 3-way 7970 Crossfire pretty much tied 3-way Titan SLI.  Paying the most for an extra 5% just proves you are bad with money. Period.

P.S.  The strongest aftermarket 670 is stronger than the strongest aftermarket 680.  Look it up, MSI overclocked a variation of the 670 lightning so much that not even an overclocked 680 could reach it (And there are 7950's that do the same thing).