Excessive heat when installed in "long board" C64s

[modeler]

Hi,

I built a few of these boards and also have one I bought from VGP while the FPGAs were not possible to buy. These work really well, but when installed in a long board e.g. (250407, 250466) they seem to generate a lot of heat. Sometimes upwards of 90 degrees Celcius:

When installed in the short board, this is not the case. I'm guessing the 12V input makes a difference, but the analogue-only version of the board doesn't get hot at all. Has anyone else noticed this and is there a real cause for concern?

Thanks.

[c0pperdragon]

The board uses a linear voltage regulator to step down the operation voltage to 3.3v. This causes quite high energy loss when used with a 12V input. There is quite a big head dissipation area on the board for this purpose. The regulator should be up to the job, anyway.
When using just the analog circuit, the power consumption is much less and the regulator has much less to do in consequence.