Got David's build below 1k with a few tweaks.
PCPartPicker part list / Price breakdown by merchant
CPU: Intel Core i5-4690K 3.5GHz Quad-Core Processor (£161.94 @ Aria PC)
CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler (£24.25 @ Scan.co.uk)
Motherboard: MSI Z87M-G43 Micro ATX LGA1150 Motherboard (£63.94 @ CCL Computers)
Memory: Mushkin Blackline 16GB (2 x 8GB) DDR3-1600 Memory (£110.27 @ Aria PC)
Storage: Samsung 840 EVO 120GB 2.5" Solid State Drive (£59.99 @ Amazon UK)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive (£36.00 @ Aria PC)
Video Card: MSI GeForce GTX 770 2GB TWIN FROZR Video Card (£218.12 @ Scan.co.uk)
Case: Cooler Master N200 MicroATX Mid Tower Case (£31.19 @ Aria PC)
Power Supply: Corsair CX 500W 80+ Bronze Certified Semi-Modular ATX Power Supply (£45.36 @ Amazon UK)
Optical Drive: Samsung SH-224DB/BEBE DVD/CD Writer (£11.32 @ CCL Computers)
Monitor: Dell U2412M 60Hz 24.0" Monitor (£185.99 @ Aria PC)
Keyboard: Zalman ZM-K500 Wired Mini Keyboard (£29.99 @ Ebuyer)
Total: £978.36
Prices include shipping, taxes, and discounts when available
GA-Z97M-G43 if you want an M.2 slot.
The N200 and the Prodigy are about the same size. If you still want mini-ITX and don't need an M.2 slot get the GA-Z87N-WIFI.
Are you going to calibrate that monitor?