G-sync

Here's an issue that should be known if it's not already, relating to G-sync. 

Displays that support G-Sync can be FPS capped at whatever the refresh rate is of the display. So for example if you have a 60hz display with G-sync, you can get a max of 60 FPS while in games/benchmarks when G-Sync is ON. In general, G-Sync is meant to provide a smoother framerate.

I'm mentioning this because I've seen a few laptops (usually those with 4k displays) come back for "GPU issues." They are usually G-Sync enabled machines, and the user is probably running a graphics intensive program that may seem to perform worse than expected because they are specifically looking at the framerate. In some cases you can expect the framerate to be lower because of a 4K resolution, but if a customer is specifically talking about a locked framerate, then it's likely G-sync is enabled. I usually see G-sync lock the framerate to 30 or 60FPS when running Valley benchmark on a 4K monitor. After disabling G-Sync, the machine can exceed past 60FPS.

If anyone runs into issues relating to slow performance in games on a new machine, check to see if it supports G-Sync. This would be listed under the "Manage 3D Settings" option in the Nvidia control panel. Some programs may not perform well with G-Sync, so disabling that may help the customer have a better experience. 

Some of this info depends on the application or hardware setup - I just want to make sure that you are aware that G-sync can usually help, but sometimes hinder performance.