Ah-ha, nailed it! Finally got it to do what yours is doing. I set x37 in bios, boots and shows x37 in cpuz, but after resume from sleep was now back to x36.
We were right, it's defaulting back to the max turbo frequency after resume, even though thats disabled in bios.
When I set mine to x37, it would go back to x36 after resume, which is the default 6 cores active turbo frequency for this processor.
The trick is to enable [auto may work also - untested as yet] turbo frequency in bios and set the active core settings to the minimum you want.
I left my 1 and 2 core as-is [39] and set all the others to 37, which is the default for 3 and 4 cores active so I could probably have left them as-is as well, but for 5 and 6 cores active the default was 36 and after setting them to 37, it will now boot and show x 37 and still be on x37 after resume from sleep.
Mind you, my systen totally spat the dummy on the first resume from sleep!!
It seem to give up trying to resume, went into bios loop a couple of times, then started with the logo but asking me if I wanted to boot from the dvd, 7x64 was still in the drive but boot order was such that this message should not have appeared.
I ignored the message and there was a momentary flash of something on the screen [bsod I think] and it booted the dvd anyway ["goddammit, what the hell are you doing!!" ]
So I ctrl-alt-del out of that, bios starts ok this time [no loops] but I'm still asked if I want to boot the dvd, I ignore, it flashes the sceen and boots the dvd again.
I ctrl-alt-del out of that again and remove the dvd from the drive while it's re-posting.
This time it pops up the boot screen for safe-normal boot etc. I tell it to boot normal [if it knows what that is anymore!!] and it gets on with the job and I arrive at the desktop with a message that windows has recovered from a problem..."you don't say!!"
I tried cpuz, still on x37 and was able to sleep/resume any number of times after that and it remained on x37 with no issues resuming from sleep....go figure!!