Is this a good gaming PC?

It's fine for gaming, but the graphics card is a bit of a letdown. I would upgrade the GPU to the new one that came out this week "GTX 10XX".
what is there already will run games at max but upgrading the GPU will future proof it
 
What you could do is either build a PC or replace the GPU with a GTX 980 Ti ( cause they are cheaper now that the 1070 and 1080's are now selling! Get an SSD and try to get them to put the OS on the SSD. Upgrade to the Asus GeForce GTX 960 OC Strix 4GB Other then that that is a great PC!