Hi Delta280,
The trace shows a very large number of interrupts being triggered and very few DPCs. That's typically a sign of a malfunctioning device from what I've seen but if you haven't already done so I'd suggest using
DDU in safe mode to uninstall the GPU drivers, reboot, and then let Windows Update install the display drivers.
If that doesn't help I'd then suspect a problem with the new GPU or possibly a problem with audio. In the roughly 4 second trace the drivers dxgkrnl.sys fired 163,654 interrupts and HDAudBus.sys fired 163,724. For comparison, playback of an HD video on Youtube and running a virus scan on my computer in a 143 second trace shows dxgkrnl.sys firing 16,200 interrupts and HDAudBus.sys firing 4,083.
Do you still have the old GPU you can try if needed?