is the AMD FX-8320 a good gaming CPU?

At the same price, actually $5 less, this is a better performing build than that cyberpower.

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4460 3.2GHz Quad-Core Processor ($176.95 @ SuperBiiz)
Motherboard: Gigabyte GA-H97-D3H ATX LGA1150 Motherboard ($87.99 @ Amazon)
Memory: G.Skill Ares Series 8GB (2 x 4GB) DDR3-1600 Memory ($46.99 @ Newegg)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($52.49 @ OutletPC)
Video Card: Sapphire Radeon R9 280X 3GB Video Card ($191.98 @ Newegg)
Case: NZXT Source 210 Window ATX Mid Tower Case ($44.99 @ Newegg)
Power Supply: EVGA 750W 80+ Bronze Certified Semi-Modular ATX Power Supply ($54.99 @ NCIX US)
Optical Drive: Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer ($18.89 @ OutletPC)
Operating System: Microsoft Windows 8.1 OEM (64-bit) ($86.98 @ OutletPC)
Total: $762.25
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-07-11 05:33 EDT-0400

Stronger cpu, gpu, better quality motherboard, ram, power supply. The way companies like that make money, they buy in bulk first off so they get parts for less than people can buying retail. I can find a no name 600w junk power supply even retail for $35-40, something like a diablotek or corsair cx. They don't list the manufacturer or model, just that it's 600w. A quality power supply can make all the difference in the world since it literally powers every component and need to provide stable, clean, ripple free power even under load.

They don't list the motherboard model, just that it has 2 ram slots which already says it's a low budget board. Most boards should support 4 slots. Every chance they get they cut corners and try to market it to sound like you're getting a bargain. Lines like 'huge 8gb memory' is deceptive. Anymore 8gb isn't a 'huge' amount of memory and it pretty standard for the majority of games. "Features gigabit ethernet for a fast wired connection" - aka a lan port and I'm sure anyone would have to dig hard to find a board that didn't have one standard on it today. It's just a matter of pointing out their marketing to hype something. Hard to tell if they threw in the keyboard and mouse (many prebuilts do, they're inexpensive accesories bundled in). Those things aren't listed in the details of the product even though they're pictured - then again unless I'm mistaken, that's an ide cable above the driver discs so I'm not really sure what's going on there. Old stock photo, bad stock photo maybe.

It doesn't take $1000 to build a budget i5 build with decent performance. For games like elder scrolls online and most others you'll want the stronger i5 cpu.

http://www.tomshardware.com/reviews/the-elder-scrolls-online-performance,3789-8.html
http://www.techspot.com/review/917-far-cry-4-benchmarks/page5.html
http://www.extremetech.com/gaming/203800-rounding-up-gta-v-on-the-pc-how-do-amd-intel-and-nvidia-perform