Gaming Annoying lag in AC Syndicate

[fossda]

System specs: OC'd FX-8320 @ 4.0GHz, R9 290, 8GB 1600 MHz RAM
With a 30fps cap, I can run AC Syndicate at a solid 30fps MOST of the time. However, at random moments, especially when riding a horse, I get sudden drops to 15fps which only last half a second before going back up to 30fps again. This is very noticeable and annoying. Any ideason how to get rid of this?

 

[Ryupower]

it a port of a game made for consoles,
wait a seen if it get fixed, Google for unofficial fixes or forget the game on pc and get it on console

also see, https://www.reddit.com/r/pcgaming/comments/3t81ww/ac_syndicate_pc_port_report/

 

[fossda]

I've installed the new AMD drivers, but the problem still occurs it's even worse on the train hideout, constant stuttering.