4th core no L3 or 3rd Core

The rig:
CPU: Athlon II X3 445 Rana 3.1
PSU: OCZ ModXStream Pro 600W
Cooler: Rosewill RCX-ZAIO-92
Mobo: ASRock M3A770DE
Ram: ADATA 4gb 1333

What I did:
I unlocked the 4th core and the CPU now reads as a Phenom II X4 B45. I OCed it using the Mobo software (OC Tuner) to 3.4Ghz. When I set the L3 to All instead of Auto it becomes unstable. I am guessing this means the 4th Core has no L3 (let me know if I am reading this wrong please).

Question:
As I mostly play games should the L3 on the 4th Core matter? Should I change back to 3 Core? Will it make a difference with OCing?
I guess I am just trying to figure out what difference not having L3 on the 4th Core will make.

Observation:
I know the Windows Experience Index is not a end all be all tool but Before I unlocked the CPU it was rated at 6.8 and the Ram 7.5, after unlocking it the CPU went to 7.3 and the Ram dropped to 7.3. Not sure if that makes any difference but thought it was odd.


PS.
When I previewed the message it did not look like the links were clickable. I used the insert URL option, should I have used something else?

Thanks for your time.
Ron