Yeah, this happened to me recently as well... in addition to what that reply above suggests, you can try the following, which worked for me:
- uninstall the AMD drivers through the Add/Remove programs
- re-install the drivers again
After doing this, the GPUs were recognized in device manager and the values showed up again in Watt Tool.
Another thing to watch out for is that there are apparently a 1 or more versions of AMD drivers that don't play will with that strap-1500 or 1750 bios mod. On my last build, i simply couldn't get my first 2 modded GPUs to work, despite what I thought was checking everything. Then i re-checked the driver version i had on my other rigs and found that it I was running 16.40 but it was 16.30 on the problem rig. The version # thing can be confusing but I'm talking about the long digit version that shows up in the software section of the settings area in the AMD software. Once I got 16.40 it ran like a charm.
One other thing... you mention copying to 1750 timing to 2000. I assume this is a GPU with Samsung memory? If it's Hynix, the correct procedure is to copy from 1500 upwards.