Balanced or High performance option on power settings?

Balanced is more for laptops. You can tune High performance too by going to advanced settings. High performance is not going to raise temps but may not lower temps to their minimum at idle. What may produce more heat is prolonged high usage in any of power modes.
 
With another, gaming account, other settings could be changed with all the stuff unnecessary for gaming but needed for normal work turned off. Trim startup programs to minim required, probably only GPU and sound settings left and that should unload a lot of memory and CPU load for better performance. Setting Advanced Power settings to CPU on 100% for minimum state and 100% for maximum state with Disk power savings off should minimize any temporary lags in games.
When you don't have top system, more powerful than needed, every little thing can help.