Question Pentium system freezes after POST

[ddybing]

Hi there.
I have an older Siemens XPERT system with a Pentium 3 500Mhz and a GeForce2 graphics card.

I got it recently, and the previous owner said he had issues installing Windows 98 on it. Said it just bluescreened when trying to install.

I've tried to do as good a diagnosis as I can, and to me it seems like the entire system is freezing randomly only a few seconds/minutes after POST.
What happens is that the screen and the cursor just freezes and keyboard no longer react, for instance NUM LOCK light on keybord no longer toggles. If I am not mistaken I think I can hear a slight change in the CPU fan speed (??) when this happens.
This can happen during the memory test, when just chilling in the BIOS or when trying to load a system from floppy.

What I've tried so far:

• CMOS reset
• Added a cooling fan on the graphics card, as it didn't have any and the heatsink felt hot.
• Added extra cooling inside the machine that blows towards the CPU.
• Tried booting the machine without a video card, the issue still persists.
• Tried disabling "External cache" in the BIOS menu.
• Disconnected all disks, floppy drives and CD drives.
• Used an ISA diagnostic card. The last code I seem to get is "FF 63" (possibly FF and 63), but this is displayed before the freeze happens.

To me, it seems like the CPU just halts randomly.

Is there anything else I can try to diagnose this problem?

Attached are two images of the system information.

https://imgur.com/a/zCgjpX6

https://imgur.com/a/R9FYlbN

 

[stonecarver]

Back in the day I remember.

Bad floppy drive or dirty drive was a show stopper.

Memory sometimes needed a cleaning with a pencil eraser.

A iffy power supply would kick the install to the curb but funny after windows installed if you put that same wonky power supply back in the machine life went on and worked. I was just the installer had issues with it.

last was a complaining Hard Drive.

 

[bwest7000]

Is it a proprietary motherboard?

 

[bwest7000]

I wouldn't worry about blowing more air towards the CPU, but I would definitely check the CPU cooler itself and make sure the heat sink and fan blades are cleaned of dust, muck, junk, and that the fan spins just fine.