AC Adapter Question

[mfm]

All regulators get warm, that's why they attach them to a heatsink.  The 7805 has thermal protection, if it was too hot it would stop working.

Still,

1) It doesn't get warm with other better power supplies

2) The other components in the console and in the cartridges don't have heatsinks, aren't made to be hot and will most likely last a shorter time because of the heat.