Activate Empy Standy List clean memory.

Theres a good guide on guru3d forum title of the post ' Windows: Line-Based vs.

Activate MSI Mode on your graphic card and make high priority its IRQ (-1).

Change all IRQ’s in Windows so no devices share the same channels, (checking if theres no corruption on shared ones) (if the graphic card is sharing same IRQ channel with other hardward or and its more than 16 on number there will be problems).

Install LatencyMon program and check if theres a big latency delay between your drivers, if there is, its a need the next step.

(at your own risk but increase performance) Disable all options for EMI protection in BIOS.Usually by years the thermal paste dry and it doesnt work as before, and the CPU or GPU will heat, also I recommend you format your OS clean state or create another User (Administrator) enter to it, and delete the old user that you were in, in this case you wont lose any program, and do the follow things: One thing is clean the dust other is change the thermal paste, I recommend you change them both CPU and GPU, on GPU dont use a lot thermal paste just the quantinity of a rice.

Quick cpu unpark your cores