There is probably a registry setting that can be changed in Windows,
but you could try using Ivo's animated start button with faster speed.
Read about it in this link to learn about animated buttons:
http://www.classicshell.net/tutorials/b ... orial.htmlI took your image and added a 1-pixel line to the very top,
that has special color codes to tell the button to have no transition delay.
It seems to work on Win 10, no time to check on Win8.1
Crossing fingers that it works for you.
If it does work, then that special extra top row of pixels can be added to any 3 image button for a fast response.
Just protect that line from alteration or it won't work. Those colored pixels have to be the exact value.