I have just upgraded from GTX1080Ti to RTX3090. A project created in IC7 and running in IC7(latest) causes the GPU to peak at 57% (GPU-Z reading) and drops between 2-5% when the scene is idle and 15-20% when working on the scene or scrubbing the time line. The exact same project loaded in to IC8 and left static, causes the GPU to run at 85% and any  movement causes the processor to max at 100% and on idle it stays there for a minute before dropping to 85%+.  A new empty project  in IC8 in HIGH with GI and view port GI enabled causes the GPU to run at 44%. In IC7 its 5%.
I have tried this with the latest studio driver and the latest game driver (using DDU to change them). Identical results.
Is this to be expected?

CPU AMD 9 5900
RAM 128GB
MB ASUS X570 PRO ACE

This sounds not normal...
Checked and got 2-3% GPU 2-3% CPU with a new empty project in IC8 in HIGH with GI and view port GI enabled...
Be sure you have "Reduce Idle Load" ticked in "Real-Time Render Options" (Preference)
When I untick that I get a boost but definitely not 44%
My specs: AMD Ryzen 9 5950X 16-Core Processor 3.40 GHz + RTX 3090 + RAM 64


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