Just came home and got some time to test a few parts I have not been able to test further on my trip.
One of them is a ASUS GTX670 2GB GDDR5 DirectCu II - this one works fine, and it was a steal for how much I paid for it ($12). Does need a new HSF though, although it passed Furmark at quite crispy temps (65*C max) but that's because I took the liberty to replace the hardened thermal paste it had with some brand new Arctic MX5.
The other is a MSI K7N2 Delta-ILSR - basically the full version to the previous K7N2 Delta-L I had - this one features a 3rd IDE port + 2x SATA150 thanks to the Promise PDC20378 controller onboard, 1394 managed by some Agere chip I think (not sure if it's the nVidia chipset that is controlling it or it's the separate Agere chip.), and active cooling for the northbridge (which I might have to replace - IIRC I had an ABIT HSF somewhere around that might fit and is active cooled as well.)
Initial testing mislead me to think the CPUs I had were all bad, but it quickly got dismissed once I took out an Jetway N2PAP-Lite and tested each CPUs in it, with each POST-ing successfully (except an mobile Athlon XP 2600+ in S462 package which I honestly don't even know why am I keeping and what benefits would it bring.).
An additional test confirmed my hunch - the original BIOS chip on the K7N2 was either corrupted or the contents were from a failed flash - this was further confirmed once I swapped the socketed PLCC32 between boards (as in using the N2PAP BIOS on the K7N2, which I knew it would work as it worked just fine on the Delta-L variant I previously had) and got the BIOS screen from the Jetway BIOS on my K7N2.
This meant, of course, I had to hotflash the old chip (not sure if this can be really called hotflashing considering I am actually using the board from which I have to hotflash the BIOS), run Flashrom and get the chip programmed. This was done pretty quickly, thanks to a spare 8GB WD Protege and a H-L GSA-H12N DVDRW. Since the drive already had a 98SE install done eons ago (it's at least three or four years old at this point), I just booted off a DVD called F4UBCD (FalconFour's Ultimate Boot CD, a quite handy disc which has MiniXP and Hiren's Boot CD in one ISO) into a live XP session, whipped up Explorer, copied the W6570NMS.780 BIOS onto the 98SE drive where I had a BIOS folder full of BINs for various mobos (ABIT, Soyo, DFI, LuckyTech, EPoX, ZIDA, Chaintech and the list could very well go on for long) along with two flashers (Uniflash 1.40 and 2.00RC, and Flashrom).
Then finally, I hotswapped once I booted into command prompt only, cd'd into the BIOS directory, then ran the command "flashrom -p internal -w W6570NMS.780". Flashrom detected my chip (some SST I don't exactly remember right now), wrote the BIN to it, verified the chip, then end. I shut the mobo off to clear the CMOS from RAM (since I didn't drop in any CR2032 battery yet), then powered everything back up, and got my board to work correctly.
In the end, here's a photo of the final result. Don't mind the CPUs down there, they were subsequently tested once I got the first working POST using MSI's original BIOS.
"Enter at your own peril, past the bolted door..."
Main PC: i5 3470, GB B75M-D3H, 16GB RAM, 2x1TB
98SE : P3 650, Soyo SY-6BA+IV, 384MB RAM, 80GB