All, we upgraded several Dell 62XX switches (6224, 6224F, 6248) to firmware 3.3.13.1.A38 and discovered a problem where when cold booting a non-stacked switch, the firmware failed to start the network ports roughly 40% of the time. The console communicated but the network ports were dead.
No more research was done as we needed to get the switches rolled out.
We rolled the firmware back to 3.3.12.x and tested roughly 20 cold boots and the switches started normally.