psija :
Hello.
I am setting up a PC and I'd like to know which GPU would be good to pair with i5 2500k.
Games I'd mostly play: CS GO, FIFA / PES 18, PLAYERUNKNOWN'S BATTLEGROUNDS (if GPU for this game wont break my budget)
Im currently looking at: GTX 760/960/10x0 or r9 270x
Budget: up to 200$ for used GPU
Well, as @kookie3010 pointed out, some of that is going to depend on the rest of your system:
-- first off, don't buy a used GPU unless you a) absolutely have to, or b) find a really great &
credible deal. For example, the R7 370 and GTX 1050 are at the same tier (http://www.tomshardware.com/reviews/gpu-hierarchy,4388.html), but because the "new" price on the R7 is so much higher than the GTX 1050 you're going to have problems finding a cheaper used one (https://pcpartpicker.com/products/video-card/#c=208,186,185,224,379,380,378,373,309,154,147,167,148,152,146,310,355,311,312,376,370,392,391&sort=price).
-- Your PSU could put a limitation on what kind of GPU you can even add in. For example, if you're using a prebuilt OEM machine (i.e. Dell, HP, etc.), you could have one of their -- hmm, "crappy" is kind of a mean word to use, let's say, "extremelyl undesireable & inefficient" -- PSUs, most likely limited to (at best) 300W & almost certainly lacking in the PCIe power connectors required by most cards (note that, aside from some of the really low power ones like the old HD 6450, I'm having trouble coming up with an AMD card that doesn't require at least 1 PCIe power connector). Luckily nVidia does have their GTX 1050 (which, like the other GTX 950 and 750Ti models, only needs the 75W that it gets directly from the motherboard), but anything more powerful (including that R7 370 I mentioned) would require also buying a new PSU. Hence @kookie3010's request for more system information about your current build.
-- Finally, depending on what kind of GPU you currently have, your budget may not allow for a significant upgrade. Generally, you want to move up at least 2 tiers on the GPU list (see above); a 1-tier jump would be OK if a) you're getting extra VRAM out of the upgrade, b) you're drastically reducing your power consumption, or c) a combination of both. For example, if you currently were using an R9 270, then getting an R7 370 would be useless; not only is it on the same tier, but the 370 is just a rebadged 270 in the first place. Going to a GTX 1050Ti might be OK, since you'd be using less power, but you'd have to make sure you got the 4GB VRAM version so that you're doubling your VRAM. Better options would be the GTX 970/1060 (both 3-tier jumps), R9 380/380X (2-tier jump), or an R9 390/390X or RX 470/480/570/580 (all 3-tier jumps)...but I'm not sure how well they'd fit into your budget.
-- Unfortunately, now is not a great time to be buying GPUs, whether new or used. The whole Etherium cryptocurrency mining craze has made most of the useful RX cards from AMD run out of stock, & because nVidia has the only counterparts their GTX 1060 cards have gone up in price as well. And a lot of the older R9 series cards are also hard to find.