[Surya Prihadi]

Hi Ricardo,

I want to share my findings, which I found by accident.
I know this is an old thread, but I hope you can be assisted.

I too have a GTX750 Ti, but my primary GPU is GTX 580.

To cut the story short and for MainConcept AVC GPU assist.
First you go to here :

https://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=904569

Look at Oldsmoke post on upsizing the OpenCL memory. Use 1,536 is enough.

You must use NVIDIA driver no newer than 331.65 ( only this 331.65 I tried work ) for the GTX750 Ti to work its GPU for Vegas Pro. However this driver, if you use a software which can read GPU models, will read GTX750 Ti as just a graphic card. Don’t ask me why it is so, me don’t know.

It is true that Vegas only love Fermi based Nvidia, like GTX570 and GTX580, and with those cards and suitable driver and older Vegas Pro like VP11 or VP12, the GPU assist is fantastic….however, once you use newer Nvidia driver than 331.65, the GPU assist will simply died down to such percentage or speed which will make u pissed.

GTX 750 Ti is actually Maxwell based GPU ( newest architecture ) and 1 generation down Kepler ones like GTX660Ti or the like, will not work well with Vegas Pro GPU assist….. unlike the 2 generation down Fermi based one GTX 570 or 580. This is why I said I found this out by accident as I would never imagine Maxwell based Nvidia will work on Vegas Pro as well as older Fermi ones.

I have 2 of GTX980 Vnidia sitting useless now…LOL, because minimum driver is way too new for my GTX580 to use its GPU in Vegas Pro. So driver is very important.

GTX750 Ti will not throttled itself like a GTX580 would in Vegas Pro, if both are using most suitable Nvidia driver for Vegas Pro. GTX580 is still my choice. However based on my test with 331.65 and that OpenCL memory size increased to 1,536 and Mainconcept AVC…..the 750 Ti can assist up to approx 24% GPU load for GH-4 3840 x 2160 MOV file of 25FPS, choosing CUDA option. If using Sony official test video, that red mercedes covertible, GPU load can be up to 40% for Mainconcept AVC and CPU load 55ish% ( i7 3930K 6 core ). However on XD CAM 1440p x 1080, GTX 750Ti does not assist at all, but a GTX580 will throttle up to 75%.

My suggestion is to google Oldsmoke ( user name ) in Sony Creative forums.
He is experiment king.
This will be good reading too :
https://www.hyperactivemusic.com/vegaspro/vegaspro.html

I am in my own dillema too. I love VP because it is so easy to use.
However with 4K now, I want newer Nvidia card with Display Port and 4K/60Hz ready for video not games, hence I have 2 x GTX980 …BUT newer Nvidia driver kill the GTX580 GPU assist capability, while new GTX980 is useless for Vegas Pro GPU assist hardware wise and will not work with older Nvidia driver software wise. So its bad luck for me … LOL.

Good luck trying out.

PS
If you are using MainConcept very often and heavily relying on it , get a used GTX580, it is worth the investment and it will work with your GTX 750 Ti. If u have both GTX 750 Ti and GTX 580, appoint GTX750 Ti as the card of choice in Vegas Pro ( I place my GTX750 Ti in 1st PCIE slot, nearest to CPU ) and when rendering using MainConcept and CUDA, both will work up to 40% for GTX 750Ti and 50-70%ish for GTX580 and CPU 55%ish. This dual working GPU load, I do not get from my older GTX650 ( Kepler based ), even with older Nvidia driver.

That Sony red car project, I can do Internet 1080P Mainconcept in 45 seconds and the XDCam one in 47 seconds with i7 3930K 6-core 48GB RAM and only mild overclock by Asus software to 3.5Ghz ( stock is 3.2Ghz ). Remember Nvidia driver 331.65 only and appoint GTX 750 Ti as GPU of choice in Vegas Pro.

Later….
SP