z640 sometimes very very slow after return from sleep

[Verell]

Normally the system is very responsive: UserBenchmark rates it PC Performing above expectations (60th percentile).

Unfortunately, bout every 4th to 6th time my Z640 returns from sleep It is running painfully slow.

By painfully slow I mean response to mouse clicks or mouse window drags is usually 5 or 6 seconds!

Keystroke and <CR> response is similarly slow!!!

To recover I either put it to sleep & wake it again, or reboot either of these has always worked.

System	HP Z640 Workstation  Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz Samsung 870 2TB
Motherboard	Hewlett-Packard 212A
Memory	128 GB @ 2.1 GHz
Display	Nvidia GTX 1660 w/2   monitors: 3440 x 1440 - 32 Bit colors, 1366 x 768 - 32 Bit colors
OS	Windows 10 21H2 build 19044.1466 Windows Feature Experience Pack 120.2212.3920.0

[Verell]

An update: I left Task Manager's performance window open. When the Z640 came up very slow the CPU CLOCK SPEED  was reported as 1.28 GHz! After a sleep cycle it displayed as 2.5 GHz.

Is there a way to increase the clock speed up to normal without rebooting or sleep cycling?

[SDH]

Try the 5 steps in the two screen captures below...