Well In you manual and online the have vendor tested to work list of all the RAM that has been tested verified to work. if your changing all 4 modules timings don't matter as your putting in matching sets of modules. You might pm rewben he had 32 GB in his. quite a few have upgraded there RAM I don't remember which all modules work as long as the timings and voltages match they seem to be successful.
G752VY-DH72 Win 10 Pro
512 GB M.2 Samsung 960 Pro
1 TB Samsung 850 pro 2.5 format
980m GTX 4 GB
32GB DDR 4 Standard RAM
Z97 PRO WiFi I7 4790K
Windows 10 Pro
Z97 -A
Windows 10 Pro