if you decide against a monitor and still want to go video card, here is a guide in US dollars that will help you out with price points and value from Tom's hardware:
(this and a cpu giude there get's updated monthly)
what I am getting at is bf4 at 1080p I confrmed doesn't need more than 2gb with my friend that has a gtx 680 2gb (used a gtx 670 before as uses amd/nvidia video cards as a side job buying,selling and trading used on kijiji) confirmed that that the game is already at high res when playing with the textures included with the game. So, if your heart is set on a newer vc for faster frame rates, then 2gb is fine. The bf4 needing 3gb of video memory is more hype than actual fact. I mean if they say a gtx 660 3gb (which is very hard to find in 3gb,mostly gtx 660's are in 2gb variants) can play it for nvidia as recommended for bf4, I can't see the worry over anything. And as for consoles, my best guess is that 2gb oif the 8 on ps4 has to used for it's own os,2gb for swapping leaving max 4gb for video, not even that. Xbox one I would see using near the same.
here's a console comparision:
Also, with nvidia cards, if you like doing game recording and showing off to friends, then you'll love shadowplay. Shadowplay uses a piece of hardware on the gtx 600 and 700 cards that doesn't slow down game play called nvenc (nvidia h.264 hardware encoder) that encodes on the fly and saves to the directory of choice. AMD cards don't have that in terms of hardware. so, if game recording don't matter, then choose what you will.
gigabyte g1.sniper 5 mb, 8gb ddr3-1866 mhz ram in dual channel,intel core i7 4790k 4.0 ghz quad core cpu, asus gtx 780 3gb vc,OCZ vector 150 240 gb ssd x 2 in raid 0 (intel raid),antec hcg-850 850 watt 80 plus bronze psu,corsair carbide 500r white case,pioneer bdr-208 15x bluray writer, steelseries 6gv2 keyboard ,seiki 39 inch 4k tv, logitech g502 mouse ,xbox 360 wired controller for windows,kingston 8gb usb 2.0 flash drive,windows 8.1 64 bit,creative labs sound blaster zxr pci-e sc,logitech s120 2.0 speakers
I'd rather walk with God in the Dark than shine in the light alone.