Aw no one is going to bite? I've setup my machine to reinstall the driver on boot so at least I don't have to remember to do it each time, though it slows the boot time considerably.
I humbly apologise to Intel, the problem was due to a conflict with the intel card and my current bios firmware.
For others who might run into this problem, I have a Clevo P150HM laptop. They don't make their bios firmware releases public so you have to request it specifically from their support team. However there is a thread here: http://forum.notebookreview.com/sager-clevo/416916-clevo-bios-thread.html which lists firmware obtained by customers. I hope this helps anyone else in this situation.
Since recently I'm having the exact same issues on my Sager NP8150 (which is basically a rebranded Clevo P150HM) also with an intel advanced-N 6230.
Might I ask which BIOS/EC versions you used to solve the problem, and how you configured your pc to reinstall the drivers automatically on boot?
I happen to have a Clevo P170HM with this exact same issue with my intel centrino advanced-n 6230 not having internet connetion. Everytime I have to reinstall the drivers and then it works again (and like a charm). But upon reboot, it's back to not working anymore.
I've been searching like mad to find a solution that is specific enough to work. This one looks like the winner!
I've found a BIOS here for my P170HM, your P150HM is there as well http://forum.notebookreview.com/sager-clevo/556299-clevo-bios-older-models.html
I've also checked with my vendor and they have the same version available for download. Going to try this solution and see if it works. I'll check back in to report.