Overclock Settings on FX6300

[Terra Firma]

I'm simply trying to understand what all the settings in my BIOS mean and if I've done this correctly.
I currently have an AMD FX 6300 stable OC to 4.5 at 1.312 in BIOS, registering as 1.296 in Windows.

The tutorials and such that i referenced always said to enable Load Line calibration, but in the BIOS for my Asus Sabertooth 990fx r2 there was no option for "enabled", there was regular-high-extreme or something like that. Another video i saw the guy set it to extreme but he had a Crosshair mobo, and I'm not aiming for ground breaking OC's so i set it to high.

Currently under full load it will reach 51C on the socket and 49C on the core, if I'm reading HWMonitor correctly.

I have a couple of questions.
Firstly, what is Load Line and do i have it set up correctly? As i said, it runs perfectly stable and I've not experienced any crashes. Actually, i had it at 4.4 at 1.276 or something like that and got crashes and changed it to this, crashes went away.
I also notice that my clock speeds will vary, they like to sit at 4514 but will flash up to 4622 or down to 4392 momentarily, it kinda makes me anxious but the vcore doesn't droop very much. Only down to 1.284 or so and only momentarily before going back up to 1.296

Secondly, from any other forum I've read on overclock results on FX, my temperatures appear to be incredibly low. 36 or so at idle, 51 at full load, and i only have an Asetek 550LC with Cooler Master Sickleflow fans in push-pull. 
These temps seem unreasonable to me, especially as HWMonitor will register the core as being at 18 or so at idle.

[Billy_Mays]

That's pretty good and you got lucky with the OC but you have more than adiqute cooling

[Terra Firma]

1 minute ago, Billy_Mays said:

That's pretty good and you got lucky with the OC but you have more than adiqute cooling

I understand, I know I probably have more headroom but my power supply isn't the best and I don't think there will be much noticable difference in real world performance between 4.5 and 4.6 or 7, so I think I'm content as it stands. 

 

The main question was what's the load line calibration setting though, and is it fine where it is on "High" how I have it set? What changes are made if I up it to "Extreme"? Why do my clock speeds jump around?