I'm sorry, not deliberately playing 20 questions, but I'm considering alternatives. Are these games also RAM-intensive or do they have small working sets?
The short answer is that the i7-4770 will play them better than the i5-2500K, but there may be a few alternatives. The new i7 4790K(Devil's Canyon) is substantially faster, for instance, and then there are the Xeon CPUs - some low-priced ones are in the range of the i7 CPUs.
Also next month Intel will announce the Haswell-E CPUs that will run on DDR4 memory and we all have high hopes for them. THere will also be 6- and-8 core versions. which may imply a significant boost for what you want.