|"The option for 200 MHz never became available until I put in the 2600+..."|
That's BS. It was ALWAYS an option. From the MSI website:
"• Supports Socket A for AMD® Athlon™/Athlon™ XP/Duron™/Sempron™ processors @FSB 266/333/400 MHz"
As a matter of fact, the CPU frequency is fully adjustable from 100MHz to 300MHz. From your manual:
"Adjust CPU FSB Frequency
This setting allows you to select the CPU Front Side Bus clock frequency. Settings:
[100MHz] ~ [300MHz] at 1MHz increment."
NOTE: I had to take a guess at which K7N2 Delta2 you have because you gave an incomplete model number. There are several versions in the Delta2 Series.
I also have no idea how you had your other BIOS settings configured & you never did state which RAM you're using...PC2100, PC2700 or PC3200?
And now that you've provided the complete CPU info, what you attemped was even worse than I had suspected. I guessed that you have a 166MHz (333FSB) CPU, but it turns out that it's the 133MHz (266FSB) version. Actually, I'm kinda surprised it even booted up at 166MHz without a voltage increase. So by raising the frequency to 200MHz, you tried to run the CPU at 3200MHz (16 x 200MHz) which is virtually impossible for ANY Athlon XP...even with a hefty voltage increase & extreme cooling!
"if it was going to damage my system, why was it available?"
It's available for 400MHz FSB CPUs, such as the 3000+ or 3200+ Barton core AXP. Or for people who know how to overclock responsibly.
I don't know what you did, but you must be leaving something out of your explanation. I'll say it again...all you did was over-overclock & make the system unbootable. But that shouldn't have damaged anything.
Take the board out of the case & lay it on a non-conductive surface. Install the T-bird CPU w/HSF. Install just one stick of RAM. Install a video card & connect to a monitor. Plug in the keyboard. Connect the main 20-pin ATX plug from the PSU & don't forget the 4-pin ATX12V plug. Before plugging the power cord into the PSU, try using the ClearCMOS jumper one last time...leave it in the clear position for 30-60 sec. Plug in the power & "jumpstart" the board with a screwdriver by momentarily touching the blade across the 2 pins that the case power switch would normally connect to. If it boots & you get a display, immediately access the BIOS & correct ALL the settings. Do NOT use default settings...manually configure the CPU & RAM.
Set "High Performance Mode" to manual & disable "Dynamic Overclocking". Set the "AGP Clock Control" to manual, then lock in the AGP at 66MHz. Set the AGP Aperture to 128MB. Disable both "Spread Spectrum" options. Manually enter the CPU voltage & CPU frequency. The "Adjust DRAM Freq (FSB:DRAM)" *should* be set to 1:1, but I don't know what RAM you have so that may not be the best choice. The memory timings should also be manually configured, but without knowing what you have, it's probably best not to make any suggestions.