Computer slows down when connected to external monitors
I am working on a MacBook Pro that has dual GPUS (Intel Iris & AMD Radeon)
The user uses 2 external monitors.
His computer starts slowing down, the kernel usage gets to 87% and oddly bounces as high as 240 %. The laptop is a bit warmer than usual but no thermal problems. The user reports that when this problem started that it was about 1 hour or so before the computer slows down; it is now starting to slow down in about 5 minutes.
The user has reset the PRAM and also SMC reset but no change.
Is this a hardware failure? Thanks