Upgrading Existing PC

death1234567

1. What is your budget? [~€750-€1000]
2. What will be the main purpose of the computer? Internet/HD/4k? Gaming and I want to try an future proof it as much as possible. I don't want to have to upgrade again this time next year.
3. Do you need a copy of Windows? No
4. Can you use any parts from an old computer? Yes, see below.
5. Do you need a monitor? Yes
5a. If yes, what size do you need - Size isn't important but I was hoping to get a 4K 144 hz moniitor if possible.
6. Do you need any peripherals? Nope
7. Are you willing to try overclocking? Yes
8. How can you pay? Credit Card.
9. When are you purchasing? in the next month or so.

Current Build:
CPU: Intel Core i5 4670K Quad Core Retail CPU (Socket 1150, 3.40GHz, 6MB, Haswell, 84W, Intel Graphics, 4th Generation Intel Core.
CPU FAN: Arctic Cooling Freezer 13 CPU Cooler
HDD: Seagate Barracuda 1TB 3.5 inch Hard Drive 720RPM
SSD: Crucial 2.5-inch 240GB M500 SATA 6Gb/s Internal Solid State Drive
Mobo: ASRock Z87 PRO4 Motherboard (Socket 1150, Z87 Express, DDR3, S-ATA 600, ATX, Haswell, Supports 4th Generation IntelCore Processors)
PSU: Corsair CX750 Builder Series CX 750W ATX/EPS 80 PLUS Bronze PSU
Memory: Corsair Vengeance 8GB (2x4GB) DDR3 1600 Mhz CL9 XMP Performance Desktop Memory Kit Black
GPU: MSI R7850 2GB DDR5 PCI-E Graphics Card

Xenoronin

4k 144Hz isn't realistic at the moment. Requires trade-offs in colour representation which are... honestly horrible to me. See: http://www.tftcentral.co.uk/reviews/asus_rog_swift_pg27uq.htm
Edit: Also it costs around 2500€ currently: https://www.amazon.co.uk/gp/product/B07BQYC65W/ref=as_li_qf_asin_il_tl?ie=UTF8&tag=tfce-21&creative=6738&linkCode=as2&creativeASIN=B07BQYC65W&linkId=4dbbd6682e88580bf3b94481eb63ae28

2k (1440p) 144Hz is realistic and super pretty.

Your build is still super solid. You could upgrade to a 1070, 1070Ti or 1080 and invest the rest in a really nice screen. You could hold off on buying the screen until black friday/cyber monday sales at this point. This specific Dell screen usually has large reductions: https://www.overclockers.co.uk/dell-s2716dg-27-2560x1440-tn-g-sync-144hz-gaming-widescreen-led-monitor-midnight-grey-mo-084-de.html

You also have the option of upgrading to an i7, though only if you see your games being CPU bound, most are not. Overclock your current CPU first. You have the cooler to push it a little harder if necessary.

TerrorFirmer

At this point the only real logical upgrade on that budget would be a 4770K or 4790K and a GTX1080Ti - though not a great time to buy a card with new cards on the horizon.

Your CPU is a bottleneck for some CPU intensive titles hence the i7. It would not make sense to pair an i5-4670K with a 1080 or 1080Ti broadly speaking when looking towards the future (though most though games will still be fine at present).

4K 144hz is also unreasonable at this point from a performance POV, as aside from some eSports titles, that requires mega CPU and GPU grunt - a 1080Ti can barely do 4K ultra @60fps in most moderm games let alone 144hz. (and I don't think anyone really buys a 4k 144hz screen to play at medium settings)

So I agree that 1440P @ 144hz is way better for that reason, and the one outlined above.

Does that 1K include the monitor? If so, I think you can get an i7-4770K/4790 2nd hand, a 1440P 144hz (non g-sync) monitor and a GTX1070 for around that. Which would all work excellently together.