It seems that you may have damaged the screen, somehow. If you make it to a repair shop, they'll be able to tell you where exactly it's coming from and whether or not it can be repaired. To your knowledge, have you knocked it on anything recently?
By using uk.pcpartpicker.com - a brilliant site for comparing and creating system parts and builds - I've discovered that the i7-6700K doesn't come with a stock CPU cooler. You'll have to find a compatible one.
http://uk.pcpartpicker.com/products/cpu-cooler/?compatible_with=tdmxFT
That link...
First question: I don't want to save up all my money for a GTX 1070 as I'd like to buy some retro rubbish so what's the best graphics card to buy for under £150 and is better than Intel HD Graphics 4600?
Second question: Old Nintendo products yellow over time due to fire retardants in the...
This falls short of your budget and it fits your specifications:
PCPartPicker part list: http://pcpartpicker.com/p/wQp2Hx
Price breakdown by merchant: http://pcpartpicker.com/p/wQp2Hx/by_merchant/
CPU: Intel Core i7-6700K 4.0GHz Quad-Core Processor ($399.99 @ NCIX US)
CPU Cooler: Cooler...
WD hard drives are brilliant and their WD Black line of drives are built for gaming & range from 500GB to 6TB.
http://www.wdc.com/en/products/products.aspx?id=760
I think it's a good monitor. Acer's a reliable brand so it'll be great. And the specs are good (and so is Overclockers) so I can guarantee you'll love it.
(I sound like a sales assistant at PC World; Jesus)