Legit Reviews

in an old old computer from a 50mm to a 40 on the CPU heatsink because the 50 was bad and rediculously loud, the 40 actually sounds normal.

is this a bad idea or does it make much of a difference(its on a slot 1 600E pentium III), and are there any signs of overheating during use, because there is no way to actually monitor the temp, i can post pix of the HS if needed

It should be fine! I have an old 450MHz Slot 1 chip here and it has no fan, just uses a large passive heatsink.
The 40mm fan will be ok!

ok, but the display was acting.. scetchy the day that i changed them when i watched a short movie (Family Guy Episode), would that be a processor problem?

It's really not the fan size all to much, but the amount of free flowin CFM over the heatsink that is required. If the 40 pushes less air than the 50, I would find a better fan. If the 40 pushes about the same as the 50, you should be ok.