Jesus, firstly the guy says he has a 4850, that will NOT be stable anywhere near the clock values given, and you're giving INCREDIBLY bad advice.
Flickering is because MEMORY clocks jump NOT GPU clocks.
YOu want to reset the profile to default, a 4850 won't be stable ANYWHERE NEAR clocks for a 5870/58xx card in general, a 4850 has significantly lower speeds.
THe reason you're crashing now is the driver is trying to use a higher clock speed that its even close to stable with AND its doing so with the lower gpu clock voltage.
All you want is a default profile, then open the profile and look for the highest memory speed, the change the other lower memory speeds to the highest setting. Memory voltage on a 48xx card doesn't go down, just the clock speeds and that does save some power, but not much. Setting all three different speeds to the highest setting will be stable, setting them above a stable setting, will not be, setting the gpu clocks to higher speeds and having the card loaded at 900Mhz(which won't be stable on that card under any load or voltage) while the voltage is (with those settings) at 0.95v which is the IDLE voltage, load voltage for stability would be 1.1v for a 58xx card.
Unless of course the OP mistyped and has a 5850, inwhich case the settings can change, but why you'd come in a thread and put up several sets of clocks and voltage options for a completely different card then only in a later post say "oh don't use those settings", I don't know, its ridiculous.
The settings in the file are now default because you've since set them there.
Some clearing up on exactly what your system is, and deleteing the profile, setting the driver to default settings, resave a DEFAULT profile with only the overdrive setting ticked and seeing what the settings in a default profile without any changes in is the first step.