First, I only chimed in because of the statement that any nvidia card would work. I don't intend to denigrate the nouveau driver, or for that matter, say anything negative about other manufacturer's gpus. I am not knowledgable about amd/ati or Intel gpus, my experience has been only with nvidia gpus for last ten or twelve years, before that I had mostly trident cards because they were cheap and I hated spending money.
I was a bit hesitant to step in here, since I didn't want to step on anyone's toes. But I remembered my dismay when I first booted after installing the gtx750ti and the screen turned into a garbled mess just as soon as nouveau kernel module loaded. I knew right then that I had not done my research thoroughly enough. If you are preparing to write a thesis, this didn't seem to be a good way to start.
The 750ti has been an excellent performer and it has served me well. But so did my quadro k600 (kepler) and quadro 600 (fermi) before that. The advantage of the kepler and fermi cards is that you would have the choice of either driver, foss or proprietary. The advantage of the gtx750ti (maxwell) is comparable or better performance with lower power usage. The disadvantage of the maxwell card is that you are forced to use the proprietary driver for 2d/3d accelleration.
There is a bit more care needed with the maxwell based card, also: you must be very attentive when ever doing kernel updates/upgrades that you also build/rebuild the proprietary kernel driver. kingbeowulf's packages for the proprietary driver are excellent and include great tools, like 'nvidia-switch' to make sure that the gl and glx libraries are handled properly. Another thing to be sure read up on, if you are not already aware, is how to prepare vanilla kernel sources for use with building out-of-kernel-tree modules. This is especially important if you decide to upgrade your kernel. To build the nvidia propietary kernel module, you must have kernel sources properly prepared... not difficult, not too time consuming, but necessary. See the
README.TXT in the distro sources. Pat sure makes it easy to do things right. But looking back to your original post, I see that you mention running a custom 3.18.16 kernel, so I am guessing that you would have no troubles with any of the kernel module preparation.
Also, I think that kingbeowulf has also given very experience/knowledge based advice about the kepler based cards. I tend to agree with him.
One thing I noticed when perusing the on-line seller I usually use: most of the nvidia cards in what I call the affordable range (less that 200$usd) mainly come with only one display port. Given the resolution you mentioned, I wondered if that would be an issue, since it's possible you are talking dual monitor and might be needing two display port connections. I often use adapters, which is what I did on my k600 card, but may or may not be acceptable for you, I don't know.
