Advice on new build

[Wabbajeck]

So I am hoping to build a new PC over the christmas break and I am trying to keep the budget around 800, but well below if possible. I have a build setup right now (http://pcpartpicker.com/p/f3Bxt6), but I am not sure if I should get another PSU of around 600w or 450w. I am also thinking about salvaging my corsair 500w pus from my old pc which has been running great for a few years. Should I salvage my PSU or get a new one, and if so, what should the wattage be? Please forgive me, I know just about nothing when it comes to PSU's, wattage, etc.

 

[PIEapple]

I would get a new PSU and change video card,R9 290 4G would be more better than GTX770 2G,2G RAM is too small,same price have more better performace
PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4460 3.2GHz Quad-Core Processor ($169.98 @ SuperBiiz)
CPU Cooler: Cooler Master Hyper 212 Plus 76.8 CFM Sleeve Bearing CPU Cooler ($19.99 @ Newegg)
Motherboard: MSI Z97 U3 Plus ATX LGA1150 Motherboard ($89.99 @ Newegg)
Memory: Corsair Vengeance 8GB (2 x 4GB) DDR3-1600 Memory ($72.99 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($49.49 @ OutletPC)
Video Card: PowerColor Radeon R9 290 4GB PCS+ Video Card ($239.99 @ Newegg)
Case: NZXT S340 (Black) ATX Mid Tower Case ($69.99 @ Amazon)
Power Supply: Antec High Current Gamer 620W 80+ Bronze Certified Semi-Modular ATX Power Supply ($39.99 @ Newegg)
Case Fan: Rosewill RFA-120-BL 74.5 CFM 120mm Fan ($3.99 @ Amazon)
Total: $756.40
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-12-02 02:03 EST-0500

 

[Alpha3031]

Here's my 2¢
PCPartPicker part list / Price breakdown by merchant

CPU: Intel Core i5-4460 3.2GHz Quad-Core Processor ($169.98 @ SuperBiiz)
Motherboard: Gigabyte GA-H97-D3H ATX LGA1150 Motherboard ($88.61 @ SuperBiiz)
Memory: G.Skill Sniper Low Voltage Series 8GB (2 x 4GB) DDR3-1600 Memory ($62.99 @ Newegg)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($49.49 @ OutletPC)
Video Card: PowerColor Radeon R9 290 4GB TurboDuo Video Card ($229.99 @ Newegg)
Case: NZXT S340 (Black) ATX Mid Tower Case ($69.99 @ Amazon)
Power Supply: Antec High Current Gamer 620W 80+ Bronze Certified Semi-Modular ATX Power Supply ($59.99 @ Amazon)
Case Fan: Prolimatech PRO-BV14 87.0 CFM 140mm Fan ($9.99 @ Newegg)
Total: $741.03
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2014-12-02 02:11 EST-0500