MacBook Pro Mid-2010 kernel panic at each restart

Question

Hi,
As most of you, I succumbed to temptation to update my MacBook Pro (mid-2010) with OSX Lion. First, I've done a traditional upgrade from Snow Leopard (10.6.8) from the Mac App Store. Due to some problems (see list bellow), I've decided to make a clean install (by extracting the file InstallESD.dmg from the Lion downloaded package. I've burned the package on on 16GB USB key (8GB is sufficient). Well.. On both type of installation I've encoutered the same problems.
The 99% of the time, my MBP make a kernel panic at the start (both when I do a simple restart of the system or after restating the system after a normal shutdown.
As I use mainly my MBP for professional use, I set the system to ask for a user logon at system start. Mainly each time, it wasn't possible to logon to the system. As soon as I tried to enter my password, I only see the game wheel icon turning on the screen and no possibility to enter my password. In this state, my only solution was to restart my system by pressing the power button.
Both of these two problem was replicable in either an upgraded system or on a clean install.
Finally (because I'm a patient guy :-) ), I've do a third clean installation, restored my system from one TimeMachine backup and found a solution to avoid having the problem I explain into the point 2.
When you restore a backup from TimeMachine from within Mac OSx, you have to create a second admin account, log onto this account and run the Migration Assistant to restore your backup. Admitting that, like me, during the clean OS installation, you've used the same account name as the one you had into your backuped installation, at the time of the TimeMachine restore, Migration Assistant will propose you two things:
Create a new user and restore our TimeMachine backup on this new username
Replace the existing username on your clean installed machine my the one that was backup into timemachine
As I've previously created a new account with admin right, I've logged on this account, launch Migration Assistant, confirm that I'm okay to restore my TimeMachine backup on the already existing user.
Finally, this setup resolved my point 2 problem. The difference between my initial setup and the one I use now is that I've now two users presented on my logging screen. To log on now, I've to choose the user, enter the password and never had the problem I had before with only one user set on my system.
Now, I really hope that Apple will fix this first version of Lion asap. For the rest, I'm pretty happy with the system. I'll work this week with Lion and will see if I encounter other problems. One thing is sure, I'll keep my TimeMachine backup of my previous Snow Leopard system at a safe place until I'll be sure that Lion will be stable.
Cheers....

Answer 1

Hi,
That's correct, I'm running with one RAM chip, after testing the bays work correctly first, I elliminated that route, so it was indeed a bad RAM chip module.
I was just about to give up, as the first swap was with the good RAM out, so same problem. I thought I had nothing to lose by swapping the RAM again, and voila, it worked. I'm opening up some seriously big photoshop files at present, just to make doubly sure it's been resolved ha ha.
I'm looking at replacing my RAM now with OWC, as apparently according to their website and with the correct EFI updates, you can max out the mid 2010 MBP with 16GB of RAM. I'll much rather treat myself to that, than forking out on a new logic board.
I think it's quite a simple, but effective fix this one.
Thanks for all the advice and help, I really did appreciate it.
Ciao,
Adrian