Wow I did not expect so many to participate, that is awesome! Thank you all for sharing your screenshots and stories.
I´ve done some more quick testing and thought about how I want to set up my charts. I think for the thermals/voltage thingy I´ll start with stock settings, then start at 1.35V and go up in 25mV steps. Like 1.35 - 1.375 - 1.4 - 1.425 - 1.45 etc. and make idle + load measurements on the temp. I´d like to use two cinebench R15 runs back to back for that because they take enough time for the CPU to heat up but are not overkill on the heat output like prime95 in small FFTs would be. I´ve seen prime95 cook my NB more than the CPU on the nForce chipsets...
But if you think that´s not appropriate, let me know what you think. I take suggestions

Same goes for the gaming tests and other benchmarks for the 2nd chart, I´m not sure about what to include. I can´t do everything of course, I sadly can´t do this fulltime. I was thinking about Half-Life 2 as a must, maybe some GTAV as a modern title. Benchmark wise I´d like to include one 3DMark Version, Cinebench and SuperPI.
And I went for the next step 1.375V on my stock E8500:
Single core test was plug and play, but getting it stable for a full CPU test was a bit tricky. It first threw BSOD, I took out my pencil and drew some more LLC on the board

It then ran the benchmark but stopped with an error at 75%, two times in a row. So I went back to the GTLrefs and played around a bit, because I have no clue what a C2D likes on those but eventually got it do some clean runs.
Temps are starting to rise, 64 °C now. (well knowing intels temp-sensors its more like 64°C-ish)
@AmioriK Yeah I love to do that comparison too, I use the quick and dirty CPU-Z bench to compare mine vs. modern CPUs at stock speed.
Really cool to already be up there competing with modern architecture. My first OC I ever tried was with first gen Ryzen and I was really disappointed. Not just by the concrete frequency wall, but also the whole process was so simple. No real tweaking to do, just raise Vcore and try it. Rinse and repeat.
With 775 stuff you got different chipsets that support DDR2/DDR3, linked vs unlinked FSB, GTLrefs, VTT voltage etc. So much more fun!
I´m still on the 780i chipset currently, because this was on my benchtable for a quick test. I want to see if it really can´t go beyond 500 on the FSB and loaded the poor thing with a full memory config in 4x2GB.
I have some fast DDR2 memory too, but only 2x1GB in 1200 5-5-5. This might work great for the CPU OC but is horrible for benchmarking more modern stuff that expects more RAM.
As soon as I hit the FSB wall on this board I´ll give the 790i Ultra on my Asus Striker II Extreme a shot and if I hit a wall there I´ll try my Gigabyte board and I think by then I´ll rather run out of thermal and voltage headroom.