fx-6300 cpu-nb voltage

What is considered the max safe cpu-nb voltage? I had it at 2200MHz @1.1308v stable, 1 hour prime95 and a couple hours gaming,
if I pushed it to 2400MHz it would fail prime95 fairly quick. My goal is to raise the cpu-nb frequency to 2600MHz or as close a I'm able to get it. At the moment I have the cpu-nb set at 2400MHz @ 1.1391v testing on prime as I type this. After reading some old post I saw RGone state he ran his cpu-nb @ 1.2825v but I wasn't able to tell what cpu he had. I'm also sure his cooling/mobo is way better then what I have.http://www.overclockers.com/forums/showthread.php/730550-Vishera-and-NB

I think I have partially found some of the answers to my question.
cpu-nb 2400MHz @ 1.1391v stable at the moment. (only stress tested for short amount of time)
cpu-nb 2600MHz @ 1.1391v fail prime95
cpu-nb 2600MHz @ 1.1419v did not boot, got a black screen had to use jumper on mobo.
cpu-nb of 2400MHz might be all this chip/mobo can handle. Is there a recommended voltage limit? Are there any other setting that can be adjusted to try to get system stable with a cpu-nb of 2400MHz stable?

I run my NB quite regularly at 1.3v+

Do you think it just needed more juice to help keep stable? Im guessing that chart is for all FX processors?

Thank you

Yes and yes, start at ~ 1.25v should get you to 24-2600 any way

I wasn't able to get the cpu-nb at 2600MHz even at 1.45v. It would fail to boot sometimes and I would have to use the cmos jumper on the motherboard. I was hesitant to run over 1.45v, while at that voltage it did make a significant difference to temps too.

Some chips just don't have the parts. Try lowering to 2400 . If it's a no go then you're pretty much done.