+3.3v line and CPU

If your +3.3v line was low but the Core volatge was on target, could you still have CPU instability?

i dont think so, because the voltage regulator on the mainboard has different outputs for both rails.
however the VIO voltage (3.3V) is the one supplied to most the components on the mainboard, that are RAM, chipset, PCI, AGP which makes it not so easy to know where the cause of instability is.

Otto is right the 3.3v has little or probably nothing to do with the CPU. But if your 3.3 is low, it can cause SYSTEM instability but not cpu. If it is too low, you may get memory errors, or you video card may decide it needs more power and freeze your system.

ok guys i have a question here. my abit board lets me change the vio (i forget the numbers but the default for me is 3.5v rather than 3.3v) what will increasing the vio do? anything? is it dangerous? what does it affect? thanks

yeah, most the new mainboards have now the default voltage for I/O set to 3.4-3.5V. as i said that is the one supplied to the chipset, RAM, PCI, AGP and some of the other components on the board - most part of the chipSet.

(un?)fortunately you wont get it over the 3.6V which is still a safe one, but, unless you really need it as high, you shouldnt raise it any further. i got mine down to 3.3V, since there is really no need to keep it high at the default 3.4V.