Need help with this peculiar problem

[Naptune]

Ok, I was using Project64 1.6 this morning, and it was working flawlessly like it has on my computer for the past month and a half. Then, earlier this evening, I tried opening up a game with Project64 1.6, and the screen would just go black after the first two screens with the developers on them. There would be a huge increase in memory usage too. Then I would get an error message saying "Project64 has encountered a problem and needs to close." After that, my computer restarted itself automatically. This happened with each game I have.

This is the first time I have ever had a problem with Project64 1.6. A previous version of Project64 works fine on my computer (version 1.5) with the same roms. I really don't know what is wrong. Here are the specs for my computer in case you need to know:

Windows XP SP2
Pentium 4 @ 3.2GHz
384 mb RAM
ATI Mobility Radeon 9000 IGP

I tried uninstalling and reinstalling Project64 1.6 but it didn't help.

Also, I ran full scans on my computer with Norton Internet Security, Ad-Aware, and Spybot and none of them detected any problems that might interfere with anything on my computer.

 

[Naptune]

Update:

I switched the graphics plugin from Jabo's Direct3D8 1.6 to Jabo's Direct3D6 1.5.2 and Project64 1.6 works once again. However, it doesn't work as good as it did with Jabo's Direct 3D8 plugin.

Is there anything that I could do to get Jabo's Direct 3D8 plugin to work again?

 

[Smiff]

have you tried turning off FSAA and Aniso using the sliders in the D3D8 plugin? that causes issues in some cases. otherwise, this is a strange problem, might be worth reinstalling latest directx and video drivers.

 

[Naptune]

Both of those were always off, and I installed the latest drivers but it didn't change anything...Thanks for the suggestion anyway.

I wouldn't mind not being able to use the better plugin if I at least knew what caused it to stop working all of a sudden.