Does anybody know how many variants there were of the Evergreen Am5x86-133 upgrade module? I've attached a photo of what I have. Do you have other variants? Could you attach your photos?

I have noticed that the 1996 REV I version comes with only a little heatsink, no fan. Would such a small heatsink have been sufficient, even at 100 MHz? Were these units failing in the field?

The 1998 REV K units appear to come with a heatsink/fan, but not the REV I's. Has anyone run a REV I at 133-160 MHz without a fan for an extended duration (months or years)? I recall the heatsink becoming markedly hot. As such, in 2nd photo over from the left, I had added a 5 V fan. I wasn't sure if the noise at 5 V was tolerable yet, so I had also installed a 3.3 - 4.0 V header as shown. Added was a trimmer to adjust the CPU voltage, currently at 3.6 V, and a beefier voltage regulator module for use at 160+ MHz. At 133 MHz or less, I figure 3.6 V for the fan is probably sufficient.

I've also seen modules from Kingston which don't bother with a heatsink at all and simply have a fan glued to the Am5x86. Talk about cutting costs!