Hello,
i stumbled across a strange performance issue between 4.14 and 4.17. Background information:
I bought a new PC and wanted to benchmark performance with U4 between my older one the new one.
Older : Old i7 4-Core at 2.9GHz, 16 GB RAM, Samsung SSD, Nvidia GTX 1070, Win 7 Pro
New : i7 6800K 6-Core at 3.4 GHz, 64 GB RAM, Samsung SSD, Nvidia GTX 1080, Win 10 Pro
Both systems are connected to two Monitors with Full HD resolurtion.
Checked both systems with 3DMark - Results are as expected with this configuration 
Now the problem: 4.17 has a performance issue.
In detail:
Checked new system with UE4 and Epics Kite Demo (A boy and his kite cinematic)
Results with UE 4.17 are strange: FPS between 5 (almost freeze) and 100 - Stats show that at low FPS, UE4 is a GPU hog: more than 150ms per frame but only 10- 15 in Draw
Low performance is always in the same scenes of the cinematic.
Results with UE 4.14 are best: average FPS is 45, min is 35, max is up to 120.
Then i checked my old system - it does of course not perform so well with the kite demo but …
Results with UE 4.17 show the same bad behaviour as with the new system: FPS between 1 (freeze) and 40
Results with UE 4.14 are for this kind of system good: average FPS is 28, min is 17, max is up to 70.
I checked a few assets from the marketplace - some show the same behaviour (4.17 bad, 4.14 good),
Engines are the standard ones installed via the launcher with default settings. I also build the demo for standalone launch in 4.17: same results.
So, the bad performance in 4.17 is not related to one particular system which points to a systematic problem with the UE4.17 engine.
Here is where i does not know how to investigate further.
Maybe someone else has experienced the same problems and can help.
Best Regards
Markus
PS: please forgive my bad english.
