Since you wanted Nvidia this is a really nice build, its also Insanely small, although it doesnt include the OS you can probably find a way to get on for cheap without piracy.
This has an SSD for boot and OS so it will have a near 10 second bootup.
You could save a bit by going AMD but if you need CUDA this is the way to go.
PCPartPicker part list / Price breakdown by merchant
| Type | Item | Price |
|---|---|---|
| CPU | Intel Core i5-4590 3.3GHz Quad-Core Processor | $187.56 @ OutletPC |
| Motherboard | ASRock H97M-ITX/AC Mini ITX LGA1150 Motherboard | $79.99 @ Micro Center |
| Memory | G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-1600 Memory | $59.99 @ Newegg |
| Storage | Samsung 850 EVO-Series 120GB 2.5" Solid State Drive | $69.98 @ OutletPC |
| Storage | Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive | $51.89 @ OutletPC |
| Video Card | EVGA GeForce GTX 960 2GB Superclocked Video Card | $199.00 @ NCIX US |
| Case | Corsair 250D Mini ITX Tower Case | $71.00 @ Newegg |
| Power Supply | EVGA 600B 600W 80+ Bronze Certified ATX Power Supply | $34.99 @ NCIX US |
| Prices include shipping, taxes, rebates, and discounts | ||
| Total (before mail-in rebates) | $819.40 | |
| Mail-in rebates | -$65.00 | |
| Total | $754.40 | |
| Generated by PCPartPicker 2015-03-07 21:01 EST-0500 |