OK .. I remember being on I9000 and also on GB bootloaders and did not get SoD, but the system was super unstable.
Then I went back to stock Eclair and updated to CM9 and then CM10. I am supe stable, but have SoD in the morning right after I unplug the charger. Then they go away.
The thing is, CM10 has GB and then ICS bootloaders, right? The Bootloader image and kernel image still show AT&T, so I am a little skeptical, but I thought I replaced the bootloaders when upgrading to CM9. Throughts?
CM10 doesn't flash bootloaders. You'll know which bootloaders you're on with your boot screen (I897 or I9000).
In my sig, there's the link for the I9000 BLs if you wanna try them (at your own risk). Although, a couple other things can be checked first: Do you have Deep Idle on? Do you OC?
Also, you can try to up your min Mhz to 200 (from 100).