I'm having the same problem and a lot of people are reporting the same problem on the steam forums. ATI R9 280X Running Catalyst 14.12 with an I7 Intel Processor and 16GB of RAM. Again, I'll submit a ticket, but I suggest you look at the number of people on steam who are also reporting this. It's really bad when someone is shooting a weapon and it just started after the patch.

@Jennifer H.</a> Please submit a <a href="http://support.rockstargames.com/hc/en-us/requests/new" rel="nofollow">support ticket</a>, so we can look into this one on one.

This isn't a new problem, it's gotten worse but there's been microstuttering since 1.27 do to the cheat detection, offline mode fixes the problem. I'm all for keeping GTA Online clean but shouldn't the people getting paid $135k a year be double checking this stuff before release?

I submitted I ticket then got some random automated answer, waiting for a legit answer, this patch simply ruined the game.