Can't speculate much on the tester stuff.....but W98 barely crawls on 64MB and works way better with double that much RAM.
Usual causes for lockups are video card issues....there may not be enough memory to run windows and keep the video stable and a temp fix for this is to go to Control Panel\System\Performance\Grahpics and move the slider down a notch or two and reboot and see if that helps straight it out while you finish trouble shooting.
You might need a new video card, or newer drivers for what's installed, or just flat out more RAM to accommodate the hardware so everything plays nice together.
You might also have a heat problem going on.....make sure all fans are clean inside, including the one on the CPU. You could also have a Power Supply on its last legs....you can look at the label on the power supply and if it's 250W or less, seriously be looking to replace it with one 350W or higher.
TONI
Hi There everyone I wonder if there is anybody out there brainy enough to help my freind has a old pc pentium 333Mhz with 64mb ram and running windows 98 that keeps freezing on him. I have done the usual scandisk defrag and even a full reformat and reinstall. So in my infinite wisdom I bought a motherboard tester to see if there was anything wrong with the motherboard. It has come up with two errors in the testing first one says "System booting. This means that the BIOS already passed control to the operation system. If no error flags sucha as memory size are set, boot via INT 19-Load system from drive A, then C; display error message if corect boot device not found. Boot system"
Error message Two "Test 8259 functionality. Test stuck NON-Maskable Interrupt bits(Parity/I/Ocheck);Verify NMI can be cleared. 8259 Interupt controller, channel 1 mask bits test." Ther trouble is I don't fully understand what it is telling me and if it can be corrected or not.Thats it boys and girls now the wait comes to see if I get any replies. Thanks to anyone who tries to reply to this message. Kindest Regards Tony B.

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