OS X Mavericks :: MacBook Pro Constant Crashes After 10.9.3 Upgrade

On 6/27 I upgraded from 10.8.x (don't remember which version specifically) to 10.9.3. Since then, my 2012 Macbook Pro has been crashing every 20-90 minutes - a complete crash/reboot. The crashes happen regardless of what apps I'm running - there does not seem to be a particular trigger. Upon rebooting, all of the open apps/windows reload and I get the standard "do you want to report this to apple" message. The only time it does NOT crash is if I'm not actively using it - e.g. if I let it go to sleep at night, it will not crash overnight.  

Everything was fine before I upgraded to 10.9.3, and I have made no other changes to my setup.  

The first thing I tried was creating a new user so I could see if the problem was isolated to my user account - the crashes persisted even on a completely new user. Next, I tried booting from partition and erasing the hard drive entirely, reinstalling the OS, and then choosing "setup from time capsule" - no dice; still crashes. Finally, I tried creating a new user and then using "migration assistant" to migrate my user info, and while the migration assistant itself worked just fine, it's still crashing. 

(Unfortunately, my time capsule backup is from right AFTER I upgraded to 10.9.3, so that might be the reason that those "solutions" didn't fix anything) 

At this point I would even be willing to start completely from scratch (at least I could import all of my documents, music, etc from my hard drive), but there is no way for me to force it to start "fresh" - if I boot from partition so I can erase the hard drive and then reinstall the OS, I can't get past the Disk Utility screen (so my only option is to set up from the time capsule!).