How would this PC handle Minecraft/Minecraft Mods?

The CPU is nearly the same as the Core i7-4770k or Core i7-4771, and the GPU is the Quadro version of the GTX 750ti. I don't see any reason for it to have trouble running Minecraft with the mods because the E3-1241 v3 can address 8 threads and it has a good chunk of processing power. It's not like you need a bunch of GPU power to run Minecraft, but running it with mods does tax the CPU to a fair degree.

If you're considering buying this rig on the used market then don't pay too much. This PC is using workstation hardware which a normal user won't be able to make use of. The only real difference between a Xeon E3 and a Core i7 is the Xeon can use ECC RAM which is of no use when playing games or watching videos. Used Xeon processors are cheaper than their Core i7 counterparts on ebay. The Quadro k2200 is worth a little bit more than a GTX 750ti, but it's not a good value for a normal consumer when compared to a used Radeon RX 570 or GTX 1050ti.