Building a new PC (First build) need advice

Im tryinng to build a good pc that can max out fc2 on 1440x900 with about 30-60 fps. This is my first build and I been looking at parts for a while now but I can't seem to know if I am over pricing. My budget isn't really strict but Im trying to get the main parts (cpu, graphics card, ram , harddrive etc.) but also win7 and a cheap keyboard and a cheap mouse all for around $850 (US). I also fly fsx and I'm thinking about getting dcs a10 or maybe a future version so I would also like to play these on a good high setting. Heres the parts that I have right now but I feel some may be unnesasary to me.

Case: Antec Three Hundred ATX

Power Supply: Antec EarthWatts EA750 750W (Is this good enough? and should I try to get a better brand? P.S I might crossfire will it be good then?)

Motherboard: MSI 870A-G54 AM3 AMD 870

CPU: AMD Phenom II X4 955 Black Edition 3.2GHz (want to keep this I feel its good for the price and it will do the job)

Hardrive: Seagate Barracuda 1TB 7200 RPM

Ram: G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 (Is this

unnecessary? Should I just get 4gb?)

Video Card: HIS H685F1GD Radeon HD 6850 1GB 256-bit GDDR5 (I really think I don't need this but I want it but would a lower price video card do just fine or should I keep this?)

Operating System: Win7 home OEM (does OEM make a big difference I don't work at home or do anything like that but I do use microsft word and powerpoints so does the default windows office that comes with win7 work fine or would I want to but microsft office)

All of the parts can be found at: www.newegg.com

I didn't include the keyboard, mouse, and dvd drive because I have no questions about it and I figured you guys didn't need to know, but its included in the price

Sub total: $864.85

Grand total: $953.58

By the way this may sound like a stupid question and probally is (im only 15) what is the difference between subtotal and grand total?

Thankyou for reading

Killa, your choices all seem ok but if you want good FSX performance and can swing it, get a decent Asus Mobo as they allow for over clocking quite well. Right now you should go with a Sandy Bridge CPU such as an i72500K or better still a 2600K, also invest in a decent aftermarket CPU cooler. Look around and you'll be able to find either an ATI 5870 or nVidia GTX470 for a reasonable price and also up the PSU to an 850W, this will allow you to add a second vid card down the road for XFire or SLI & multiple monitors ;) Definately go with 8 gigs ram but if you do build a SB i7, all the ram in these systems runs at low voltage so it doesnt get too hot, so u don't really need the expensive ram with heat spreaders etc...

This should all fit in your budget and will future proof you for awhile. As for the total sub-total thing, it's probably taxes. Good luck on your build.

Oh also go with the 64 bit Windows7.

Hope this helps.

The thing with intel processecors is they always seem to get the price sky high when i try the i5 and i7. I know they are better but the price always goes up

Yeah typically that's true but with the new line of Sandy Bridge CPU's the price point is very attractive, especially given the overclocking potential.

I bought an i7 2600K for $300 and I'm so happy that I went this way, the performance increase over my Phenom X4 960 is unbelievable.

Duke has given good advice and I could second that.

I agree the Phenom II Architecture is getting pretty old and soon the Bulldozer and Llano's core's will be out in full. If they are any good they might drive the price of the sandy bridge processor's down a little or the price/performance ratio might have you picking up a bulldozer core.