Im looking to build a gaming rig with a monitar, keyboard, mouse, and os and my budget is around 800

Solution
Anyway you could get an i5 for your budget:

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4440 3.1GHz Quad-Core Processor ($184.99 @ Amazon)
Motherboard: ASRock H81M-HDS Micro ATX LGA1150 Motherboard ($49.99 @ Micro Center)
Memory: G.Skill Ares Series 8GB (2 x 4GB) DDR3-1866 Memory ($58.98 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($47.99 @ NCIX US)
Video Card: Gigabyte Radeon R9 270 2GB WINDFORCE Video Card ($159.99 @ Micro Center)
Case: Corsair 200R ATX Mid Tower Case ($49.99 @ Amazon)
Optical Drive: Samsung SH-224DB/BEBE DVD/CD Writer ($14.97 @...
Anyway you could get an i5 for your budget:

PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4440 3.1GHz Quad-Core Processor ($184.99 @ Amazon)
Motherboard: ASRock H81M-HDS Micro ATX LGA1150 Motherboard ($49.99 @ Micro Center)
Memory: G.Skill Ares Series 8GB (2 x 4GB) DDR3-1866 Memory ($58.98 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($47.99 @ NCIX US)
Video Card: Gigabyte Radeon R9 270 2GB WINDFORCE Video Card ($159.99 @ Micro Center)
Case: Corsair 200R ATX Mid Tower Case ($49.99 @ Amazon)
Optical Drive: Samsung SH-224DB/BEBE DVD/CD Writer ($14.97 @ OutletPC)
Operating System: Microsoft Windows 8.1 (OEM) (64-bit) ($93.99 @ NCIX US)
Monitor: Acer UM.WV6AA.B01 60Hz 21.5" Monitor ($112.48 @ Amazon)
Keyboard: Cooler Master CM Storm Devastator Gaming Bundle Wired Gaming Keyboard w/Optical Mouse ($27.85 @ OutletPC)
Total: $801.22
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-03-10 04:51 EDT-0400
 
Solution


D'oh! well spotted

This is the minimum I'd recommend: http://pcpartpicker.com/part/evga-power-supply-100b10500kr

$45 with $10 MIR. If you can spend a little more then this a better quality PSU: http://pcpartpicker.com/part/xfx-power-supply-p1550sxxb9

$54 with $10 MIR

PSU added + a couple of tweaks:
PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4440 3.1GHz Quad-Core Processor ($173.99 @ SuperBiiz)
Motherboard: ASRock H81M-HDS Micro ATX LGA1150 Motherboard ($49.99 @ Micro Center)
Memory: G.Skill Ares Series 8GB (2 x 4GB) DDR3-1866 Memory ($66.95 @ OutletPC)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($47.97 @ SuperBiiz)
Video Card: Gigabyte Radeon R9 270 2GB WINDFORCE Video Card ($157.99 @ SuperBiiz)
Case: Enermax OSTROG ATX Mid Tower Case ($39.99 @ Directron)
Power Supply: XFX 550W 80+ Bronze Certified ATX Power Supply ($53.99 @ NCIX US)
Optical Drive: Samsung SH-224DB/BEBE DVD/CD Writer ($12.99 @ Newegg)
Operating System: Microsoft Windows 8.1 - 64-bit (OEM) (64-bit) ($92.00 @ B&H)
Monitor: Acer G226HQLBbd 60Hz 21.5" Monitor ($94.99 @ NCIX US)
Keyboard: Cooler Master CM Storm Devastator Gaming Bundle Wired Gaming Keyboard w/Optical Mouse ($27.85 @ OutletPC)
Total: $818.70
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2015-03-16 04:14 EDT-0400

This is just under $800 afer rebates. If you can spend an extra $30 then I would swap the 2gb R9 270 for a 3gb R9 280:
http://pcpartpicker.com/part/msi-video-card-r9280gaming3g