New build, will it work?

Yep, it will work. Just so you know this is better than a medium level gaming system. This will max out any game, there are only 6 or 7 gpu's out there that are stronger than this. I would say the first mid range gpu is a 7770.

Yeah I kind of thought so too. Any specific recommendations for gpus more in the medium range?

What is your monitor resolution and what games will you be playing? Your build is good for your budget and the 7870 is a great card that will play most games on the highest settings at 1080p. Don't drop to a 7770, you will be disappointed with the performance, a 7850 can be bought for around the $200 mark and would be the minimum you should aim for.

I guess you could go for a 7850 but I still consider that high end and will still max out most games. The 7770 is a good card and from what I have read performs well. But I say if you can get why not just go with a 7870. I plan on getting one soon and I fell like it is one of the best valued GPU's on the market right now. It is stronger than a 660ti but is $40 cheaper than it in general.

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Cooler Master HAF 912 Mid Tower Computer Case (RC-912-KKN1)

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Corsair CX 750 Watts 80PLUS Bronze Certified Modular ATX12V/EPS12V Power Supply CP-9020015-NA

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ASRock Z77 Extreme4 LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
Microsoft Windows 7 Home Premium SP1 64-bit - OEM

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Intel Core i5-3570K Ivy Bridge 3.4GHz (3.8GHz Turbo) LGA 1155 77W Quad-Core Desktop Processor Intel HD Graphics 4000 BX80637I53570K
Sony Optiarc 24X DVD Burner, Bulk Package Black SATA Model AD-7280S-0B - OEM

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MSI R7870 Twin Frozr 2GD5/OC Radeon HD 7870 GHz Edition 2GB 256-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card
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SanDisk 128 GB 2.5-Inch Solid State Drive (SDSSDP-128G- G25)

Total: $1,108.36 *not including shipping & rebates

Either drop the SSD or switch out this card and RAM for that 7870 up above. Personally I would drop the hard drive and keep the SSD. That way when you guy a hard drive later on you don't have to reload Windows.

The total with the switch out would be $1,027.36 *not including rebates.

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