RAM slots
RAM slots
No change other than reducing upgrade choices since you need to remove most or all of the sticks.
In both scenarios you'll be using dual channel operation. You might see improved performance by running either dual-rank modules or two single-rank modules per channel. With most systems now using up to 8GB modules, running a 4x4 configuration could enhance performance for workloads that benefit from it. Of course, if the modules are otherwise identical in speed and timing.
Will 32 GB of RAM make a noticeable difference for light gaming on this motherboard?
2x8 slots in positions 1 and 3 or 2 and 4 cover everything you require for any gaming session.
The choice of vendor type doesn't significantly impact the overall outcome for Corsair Vengeance.
Corsair Vengeance works well. Make sure the clock settings in the BIOS align with the RAM you have.