4K screens are becoming less exotic and not that crazy expensive these days, so I’ve purchased one. There are tons of reviews and discussion about digital interfaces, cables and video card requirements for gaming, but I had hard time trying to figure out video card requirements for desktop and finally learned it hard way: screwed my first config.
The thing heavily discussed in the Internet is cables. For sure, it is important, because neither HDMI or DVI is capable of running 4K at 60Hz, but basically universal solution is simple: Display Port connection between video card and monitor. More expensive option is HDMI 2.0, but it is rare at the moment.
Video memory size
This was real issue I faced with. I never cared about memory size and thought it was just about gaming. I write code, surf the Internet, but games… haven’t touch for a while and skipped all those articles debating how much memory should video card have and how many of them you have to purchase to run particular game on 4k screen. Back in days I used built-in video card in my processor and never got any memory issues. Then I have to purchase cheap NVidia Geforce 630 card for my monitor with 2560*1440 resolution. It had 1Gb of memory and it was enough for my needs.
So I purchased cheapest possible card with Display Port to drive my 4K screen - NVidia Geforce 750GTX with 1Gb RAM. My current setup includes 3 monitors: 24” FullHD (1920x1080), 27” 2560x1440 and 28” 4K (3840x2160) running on Windows 10. At first I had very mixed feelings. 4k is super awesome, but I noticed how Windows UI became slower, screenshot tools start to work with noticeable delays or crash, even browser scrolling was no longer smooth and sometimes I got spontaneous short freezes in various apps. 4K video on YouTube looks like fast slideshow. It turned out video card memory usage was close to 100%. If I lowered 4k screen resolution or turn off other monitors, UI became significantly faster.
After series of experiments I’ve come to conclusion, 4k screen alone can hardly fit into 1Gb limit, especially if you open several tabs in modern browsers with hardware acceleration enabled. Browsers alone can easily take 500Mb of video memory. I ended up upgrading my video card to NVidia GTX 960 with 4Gb memory onboard. This is completely different experience: 4k YouTube video just works, UI is fast, browser scrolling smooth and screenshot tools work much faster, comparing to 1Gb memory card. During my daily usage typically video card memory usage is about 2Gb of video memory and if I use Jing to take a screenshot, it can peak up to 3.5Gb.
Based on my experience, 1Gb is absolutely minimal if you have single 4K screen. If you have multiple monitors - 2Gb is minimum amount of video card memory and you probably should consider purchasing 4Gb card.