This is ~$588 post tax assuming a 10% tax rate (I googled, it's lower in Ohio but fuck it, wanted to be safe.
PCPartPicker part list / Price breakdown by merchant
| Type | Item | Price |
|---|---|---|
| CPU | Intel Pentium G3258 3.2GHz Dual-Core Processor | $66.98 @ Newegg |
| Motherboard | Asus B85M-D PLUS Micro ATX LGA1150 Motherboard | $44.99 @ SuperBiiz |
| Memory | G.Skill Ares Series 8GB (2 x 4GB) DDR3-1600 Memory | $29.99 @ Newegg |
| Storage | Western Digital Caviar Blue 500GB 3.5" 7200RPM Internal Hard Drive | $42.90 @ Amazon |
| Video Card | Sapphire Radeon R9 270X 2GB Vapor-X Video Card | $182.98 @ Newegg |
| Case | Thermaltake Versa H25 ATX Mid Tower Case | $24.99 @ Newegg |
| Power Supply | EVGA 500W 80+ Certified ATX Power Supply | $34.99 @ NCIX US |
| Optical Drive | Asus DRW-24B1ST/BLK/B/AS DVD/CD Writer | $15.99 @ Newegg |
| Operating System | Microsoft Windows 8.1 OEM (64-bit) | $84.89 @ OutletPC |
| Keyboard | Logitech K120 Wired Standard Keyboard | $6.99 @ NCIX US |
| Mouse | Logitech B100 Wired Optical Mouse | $6.89 @ SuperBiiz |
| Prices include shipping, taxes, rebates, and discounts | ||
| Total (before mail-in rebates) | $590.58 | |
| Mail-in rebates | -$55.00 | |
| Total | $535.58 | |
| Generated by PCPartPicker 2016-01-20 03:23 EST-0500 |
You will have to overclock the G3258, and it will be a little noisy on the stock cooler, but should OC okay. If possible, consider reusing your HDD. The R9 270X should be a bit more powerful than the 750Ti, and should run nicely on a 500W PSU.