Overclock: mp4 playback is now rubbish

[getho]

Just overclocked my 5820 to 4.2Ghz.  I've tested it, seems very stable, temps are fine, no throttling. DRAM now at its stock speed of 2400, rather than 2133 that "auto" was setting it to. 

Rendering seems improved, general system responsiveness is good... BUT whereas premiere used to be able to handle mp4s with no problem, now it stutters and spits the dummy - even 1080 ones seem to give it trouble. A  higher res timelpase (4k) - I have to wait 30 seconds before I get a single frame displayed in the source monitor - it just says media pending. Even a 1080 one it taking 10 seconds+.  Once loaded the 4K one plays OK in the source monitor, but drag it to a 1080 timeline and the playhead will move, but it'll just show 1 frame.

Anyone else out there overclocking and can help?

[masai91]

This might be related to the AVX instructions being disabled when you overclock. I'm not sure about your CPU but I know that when overclocking non K Skylake CPU like i5 6500 the CPU disables some things, one is Intel AVX. From some research I found it's used by Premiere, After Effects, Photoshop and so on for various things, one being h264 and mainly h265 decoding.

I was looking if someone experienced this issue, but the only thing I found was your old question. Did you finally found a solution?