Overclock ACA620 to 25mhz

[F0LLETT]

Not knowing enough about circuit design, if I put a small fan in and attach it to +12V FDD connector and the "ground" on the switch (which is attached via cable to the ACA ground/negative), would this cause any damage?

Just stick to floppy connector. All connections needed are there, +12v and Ground. So when machine is turned on, fan comes on.
Also might be worth noting, if you do not have good grounding (via the ground cable that comes with ACA) to the ACA620, then it will cause freezing / crashing issues.

[F0LLETT]

Sorry, Ground lead, bad choice of words.

The two screws go into the ground plain. However I found in some cases an extra earth was required. I was thinking of Indivision, ACA doesn't come with ground lead.
I remember having a discussion with IC about including one.

[F0LLETT]

I didn't get any screws with my card. All i got was the card. Was I supposed to be provided with screws like the ACA630? The instructions didn't mention screws either iirc.

You must have an early version of board. As new ones have screws.
This must have been the discussion, to include something like that to screw into ground.
Giving you the extra grounding point.