Hi everyone !

Usually I'm good enough at troubleshooting, but this time I don't know what to do next.

I recently built a Pentium III era machine with new old stock and used parts, I called it the "Uncle build", the kind of build your hypothetical cool uncle made for you with some old PC parts of his to play 1996-2000 era games.

• Motherboard : MSI 6309 Rev 2.0 (maybe 2.0B, not sure)
• CPU : Socket 370 Coppermine Pentium III @667Mhz
• Ram : 1 stick of 256Mb 133mhz.
• Storage : A random 500Go SATA hard drive connected with an IDE to Sata adapter, my C: partition is 127Gb
• GPU : Nvidia Geforce 4 440Mx
• Sound card : Integrated in the motherboard
• OS : French Windows 98 SE with Windows 98 Plus! installed and the USB Mass media driver.

The computer works great for what I ask for, except when I want to play Descent : Freespace

The game launch well, I can see the FMV intro, and skip it without problem.

I can chose my profile, click wherever on the menu to go to the options, or to chose a mission in career mode.

But every time, almost like a clockwork, after 5 to 7 seconds the game starts to ignore any keyboard or mouse input.

The pointer still moves, and I can hear the chime of the buttons on the UI when I hover my mouse on them, but no amount of clicking, swearing, praying the computer gods makes any difference, I'm kinda soft locked into the game. Sometimes I can regain control by pressing to many keys on the PS/2 keyboard, and I can start a mission, but then the keyboard controls lock themselves for a few seconds every minute or so, making the game pretty hard to play.

Here is what I tried :

• First I was using Windows 98 SE Vanilla, I tried to apply a crapload of Microsoft patches, and even the Plus! pack.
• I updated every driver I could find, and made sure that the device manager reported no error.
• I tried with a PS/2 keyboard and mouse, then a USB keyboard and PS/2 mouse, then both USB, the problem is still there. The only difference I saw is that when I press to many keys on the PS/2 keyboards the motherboard beeps, and sometime I regain control and I can alt-tab or quit the game.
• I saw some forum posts about an issue with the game resolution not matching the desktop one, so I tried launching at 640x480, 800x600, 1024x768, and 1280x1024. No difference
• I updated the game with the latest official patch, from 1.0.2 to 1.0.6.
• I tried to disable every port that looked useless to me in the BIOS, all the serial ports, the parrallel port, the on board modem, etc...
• I upgraded the bios from version 3.0 to 3.8.
• I tried to force my way into a mission and use a game port joystick, same problem.

I'm now lost. I can play Age of empire II for as long as I'd like, but Freespace does not want me to play.

Random pieces of information :

I tried to install some leftover not tested PCI cards : a Sound Blaster Live! and a PCI USB 2.0 4 ports, both of them did not work. I removed them and didn't test them on other PCI ports.
I did buy 2 identical motherboards, but tested only one at the moment.

What do I miss ? How can I troubleshoot this further ?