There is no GPU decoding activity at all when I play back the timeline or in the trimmer window. :-p
Clearly there is substantial benefits from using the GPU for decoding the playback during editing in the trimmer and timeline?
davinci resolve timeline playback has a cpu & gpu signature like a media player, it does the GPU decoding & it's really impressive. It means I can edit 4k30p footage on my slow i7 & get timeline playback of 30fps using only 35% cpu and under 20% gpu. Same file with vegas 1fps 100% cpu & it's not usable.
With all the problems of v16 & yet to date only 3 revisions, it would seem unlikely they have the ability to improve efficiency
Unfortunately full GPU use is only in the pro version at 300 USD and it can't even be validated in any way as far as I know without entering a license key. So, yes I have heard that Resolve is the most GPU friendly software at the moment.
1) It is not 100% cpu. It is CPU for media decode, and gpu for timeline processing (FX etc.) Try for yourself. Compare cpu/gpu usage during playback with no fx to payback with many fx. Try a few different ones as not all are gpu accelerated and some use it more than others (e.g. neat video).
2) DR does use the gpu in the free version, just not multiple gpu's. Again, a simple test will prove this (turn on/off in master settings and test a timeline loaded with fx.)
Can you upload (dropbox?) a sample of the media type that only gets 1 fps in Vegas and gets full playback in Resolve?
I used losslessCut to edit out a piece for you to test but surprisingly I can playback the 30second clip just fine in vegas15 no dropped frames 60%cpu 12% gpu, but the full video is unplayable in vegas.
Actually I started a new project with the same original video file & timeline without any plugins. It is working just fine (60%cpu) yet unusable last time I tried. I falsely maligned the good name of vegas!
Thanks for your honesty. Sounds like you may have some issues to work out with your setup. :)
FWIW, my 8 year old system (specs in signature ) gives me a decent editing experience (not great, but workable) with UHD footage in Vegas (14 or 16), but is unworkable for editing in Resolve. The Windows 10 CPU/GPU usage signature for simple payback is quite similar for Vegas / Resolve / Premiere (something like 20% CPU, 10% GPU) with the only major difference being that Resolve is very aggressive about grabbing Video RAM (grabs all 4GB right away) whereas Vegas sometimes grabs very little VRAM or ramps up slowly.