Lockups - spinning beachball of DOOOM!

[dnanian]

OK. What about external drives and network mounts?

If you're not running any low-level software of note, it's likely you have a hardware problem. It could be all sorts of things, unfortunately, and diagnosing it without the machine is difficult at best.

It might help if you could get things into the exact setup you usually use during backups (especially failed ones), and then generate a System Profiler report. To do so, run System Profiler, choose File > Save and then save in the default (XML) format. Once done, Control-click the resulting file and choose "Create archive...", then take the ZIP file generated and send it into support. I'll take a look.