Another thing I have noticed for balls to the walls max oc the easiest way I can do it is set all voltages to auto except vcore, vmch, vdimm (and associated vdimm reference voltages).
This is just for benching and stuff as it will run a few voltages a little to high for 24.7 but (just IMHO) it doesnt seem to really hurt anything for short runs.
The ram may be a big issue as well. Ive still got some old ballistics that I use for benching and stuff, they have done 683mhz at 5-5-4-10 for me 2.42vdimm for short runs.
Still if your sig is all the hardware you have be careful as it sucks when you fry something playing around and have to wait on ordering new stuff lol (ask me how I know)
go on, how much have you fried