If that's actually blowing the correct direction then you might want to seal the gap between the fan and the mount with something like tape or foam to reduce the amount of air that escapes before reaching the heatsink.

The way your manual is worded, it sounds like they weren't able to actually test 450 & 500MHz CPUs. It may or may not work, and a BIOS update may or may not be required.

Edit: Both of my i440BX motherboards supported 450MHz PII-450 and PIII-550 CPUs, and I'm not sure the manual mentioned the latter.

HunterZ wrote:

I sometimes put my hands along the edges of the heatsink as well to see if I can feel air coming out from between the fins.

It's safe to say that everyone here's had to find an answer to this particular question 🤣.

What I do is make a strip of paper and hold it (preferably vertically) close to the fan. If it moves toward the fan, the fan is sucking and if it moves away from the fan, the fan is blowing 😉
You could even hold a piece of toiletpaper to it, or even keep the fan horizontal, put a small piece of toilet paper on it. If it blows away, the fan is blowing and if the fan is sucking, the piece of toiletpaper will fly into the fan, causing it to jam which will overheat the copper coils, causing the ultra thin wires to melt and causing a short inside the wall...Burning down the entire neighbourhood!!! THOUSANDS OF PEOPLE TRYING TO FLEE THEIR HOMES, CAUSING TOTAL MAYHEM ON THE STREETS!! MILLIONS OF PEOPLE WILL DIE AAAHHHHH!!!

So whatever you do, make sure you point the fan in the right direction and all shall be alright 😁

Here comes the necro bump of the year

I also had problems with getting this board running with a katmai, in my case a p3 600

Its possible to crossflash with the AMI bios for the retail MSI 6119
I have not tried the award bios.

There are a few issues though, you pretty much have to stick to default values in the bios.
The exeption beeing that you need to disable all power saving stuff.
You also need to disable all powersaving stuff in windows 98 if they are installed (in the device manager)
Otherwise the system will hang as soon is it tries to use power saving, even if it only is turning of the monitor.

Other than that, everything works great.