Found something:
by Zen1 » Sat Apr 11, 2015 8:08 pm
So, I've been working on this project for a while and I just wanted to share my results as there hasn't been much interest in overclocking the BCM2836. Today I managed to overclock my Pi 2 to 1500MHz and I just wanted to share to see if anyone else was interested. I removed L3 and soldered a lead on to the pad nearest C7 so that I could apply a separate core voltage. Using the software overvoltage setting of 8 only brings you up to 1.4V. I used an EVGA epower unit to provide a clean 1.66V. I used liquid nitrogen to cool the chip with a custom made CPU pot I designed. I had to use an extension cable for the SD card as it was getting too cold and I applied a heating pad to the bottom of the board to assist with keeping the RAM warm and defrosting the board. I found the chip coldbugs at -130C and refuses to boot under -90C. I found keeping the ram above 20C helped a lot with booting and stability.
So this is just a teaser to see if there is any other interest out there and to see if anybody knows of anyone who has gone further than this.
https://www.raspberrypi.org/forums/v...?f=29&t=107149
I'll look deeper into this tomorrow.