The option for GPU Acceleration is used for the better performance of Lightroom 6.
Please go to the following link to see the list for supported graphic cards : https://helpx.adobe.com/lightroom/kb/lightroom-gpu-faq.html
Please let us know if it helps.
This is explained in some detail by a Lightroom developer
No one can really tell you exactly how much speed improvement you can expect on your computer. But, as stated clearly at that link:
The GPU performance improvement in Develop is more noticeable on higher-resolution displays such as 4K. The bigger the display, the bigger the win.
Lightroom CC/Lightroom 6 now has the ability to use the graphics processor on your compatible video graphics card to speed up adjusting your images in the Develop module
If you are going to have a compatible card for Lightroom 6 then it will definitely going to enhance your Lightroom performance.
Please check the below article to check Lightroom GPU requirements:
Thanks so much for your replies... I guess I read through the notes on possible speed improvements & read the mention of 4K displays (I'm only developing @1920), so it made me wonder how much of a boost I might see.
Any guesses from that or anything else?
Why don't you describe in a lot more detail the problem you are having?
Also, do you do a lot of brushing or spot healing?
It's mostly a speed problem when moving between images while in the develop module (the lag before the sliders become active). If I could reduce this lag, I would be happy.
The article I linked to said specifically that the graphics card acceleration would make moving beetween photos slower.
You didn't answer the question about are you doing a lot of brushing or a lot of spot removal?
OK, I see the point now, image switching in develop may take longer... Bad deal. That, I think answers my question... & to answer your question, no I'm not doing spot editing etc... or at least, I'm not concerned with this overhead.