@Susquehannock - The default TDP for a W3680 is 130 Watts.
https://ark.intel.com/products/4791...12M-Cache-3_33-GHz-6_40-GTs-Intel-QPI?q=w3680
Your XTU screenshot shows Turbo Boost Current Max = 130 Amps and Turbo Boost Power = 110 Watts. Your numbers as reported by XTU seemed to be reversed. I installed XTU on my T3500 and it also seemed to be reversed. Time to do some digging.
Here is what the Intel docs show.
MSR 0x1AC contains both of the power limits. According to Intel, the lower bits contain TDP and the upper bits in that register contain TDC. I installed RWEverything so I could have a look.
The lower bits in my example contains 0x5F0 which equals 1520. Divide 1520 by 8 and you get 190.
The higher bits contains 0x370 which equals 880. Divide 880 by 8 and you get 110.
In other words, my CPU is set to 190 Watts and 110 Amps. It is nice that the latest version of XTU supports these old X58 CPUs but it would be even nicer if the programmers read their own documentation.
Anyway, if you look at my screenshot, by disabling all of the C States, I was able to lock my CPU at a steady 4.00 GHz at idle or full XTU Bench load. I thought for sure I was going to kick some butt but the numbers do not lie.
I am down 20 points compared to your score. Windows 10 does not seem overly bloated. Maybe it was sending a few GB of data up to the Microsoft cloud while I was busy benching. Now I have to go install my old Windows 7 drive to try and find where the lost performance has gone. Cinebench score is also down 30+ points since "upgrading" to Windows 10. Kind of like bolting on some performance parts to your car and you end up going slower.