754 Ultra MS-6561 Windows crash and now sometimes doesn't POST

Question

Bought a new MSI motherboard and installed everything that's in my signature.  Everything is used except for the memory and the mobo.  The computer was running fine for a few weeks. No problems. Only recent installation is an old game: Independence War 2, where it would freeze or crash to desktop.  Didn't think much of it, as I hadn't patched it yet.  Then yesterday during lunch I tried to turn on the computer and got the following error before it got into windows:
"While Initializing device IOS:
Windows protection error. Please restart your computer."
So I restart and the computer wouldn't POST. After a few tries, it POSTs but I got the following error:
"Invalid VxD dynamic link call to device 3, service B. Please run windows set-up to fix."
So I have to restart again, and it wouldn't POST. It's the same thing over and over, it would start up and hang before POST, the display doesn't even turn on. Waiting a while and trying again will result in it POSTING. I check the tempurature of the processor and it's a cool 43-50 degrees celsius, never going higher than 65 degrees celsius on a normal day.
It will let me into windows sometimes without errors, but it will crash and then won't POST for a while. One time I was able to get to the command prompt and while trying to see a directory, it froze and bunch of symbols were all over the screen. And then at restart it wouldnt POST. But if I let it sit, it will start up no problem. But it will crash after a while.
I get home from work yesterday and decide to do the following: run scandisk, update the BIOS to 1.7, update my video drivers, and reinstall Windows 98SE.
Mind you, the day before I could barely keep the computer on, let alone try to do anything on it. But when I turned it on last night, it seemed like it was back to normal. I was on it for like 2 hours doing everything to it. I ran the scan disk and it worked fine.
The bios update went without a hitch. When I reinstalled windows, I didn't format the harddrive and only installed it over the existing 98. Why? Because I have no idea how to format a harddrive and I don't have the Win 98 cd (my bro in law, when installing it the first time on my old 450, put all the CAB files and whatnot in a directory and I installed it through there).  
I do everything else and leave my computer running for a little while. No problems. It seemed like it was running as new. I was even getting better resource management by 1% (no big deal I guess). I start up and shut down a few times to make sure I'm not crazy and it really did seem like it was normal again.
Then I shut down and go watch tv for a little while. I come back to it later, and BOOM. Same crap as before: Windows protection error, please restart. If not, it's the dynamic link VxD crap that tells me to run windows set-up.
It doesn't even let me into Windows thru safe mode. Going step-by-step start up, it seems to crash and shut down at loading windows GUI. Then it won't let me post for a while, like before.
I download memtest as I saw in one post here and as it's doing it's test I get the same thing I get when I'm in DOS:  Freezing and funny symbols on the screen.
D-Bracket, when it hangs either is at:  Full Red (processor info), or will jump from the memory test to the early chipset initialization, then back to the memory test lights.
I'm at my wits end.  Please help?

Answer 1

Thanks, Wonkanoby.  I had seen that already (one of the first things I did when I saw those errors was to go online from the work computer and look for what those errors meant in windows support).  When I was able to get into my computer, I used msconfig and saw that my system.ini was fine.
I haven't tested different ram yet, though.  Which one do you all suggest?  What I have is kingston, but it seems that some of the MSI boards don't like them.
And although it wasn't suggested, I changed the power supply as I saw that many of the problems on here were associated with it.  I got an Antec True 430.  Sure enough, it wasn't the problem :(  Still debating if I should keep it over my 330 watt (also Antec) or return it and get dinged with the 15% restocking fee.  I may be upgrading to a 2600 soon I may keep it.
I'll try the new memory this weekend.  Meanwhile, any other suggestions would be appreciated.