> AHA! So NEED to have that splitter on even if at this point I don't need the mouse functionality?
Not necessarily. Most PS/2 keyboards will work when just plugged into the IO without a splitter.
> I have also read about doing TAB+4(4 times) etc in various different flavors, what does this refer to then?
To get into the BIOS, you have to use one of the standard sequences (CTRL + ALT + ESC, DEL, CTRL + ALT + S, etc.). This is a prerequisite for changing the settings to allow a hard disk to boot. However, a V5 BIOS will not allow you into the setup screens, and will have to be physically removed and flashed elsewhere. Luckily, this is not difficult, since the epoxy was omitted on V5.
The TAB-4444 sequence was to get to a shell prompt in QNX. It is relevant for V2, V3 and V4, but only after you have already booted from a hard disk containing the modified V2 QNX image. Then, you can login as root, and run QNXflash to flash the BIOS back to V1, and proceed.
> I realize that I don't NEED to know what version I have, but the point of this excercise (for me) is not so much to just buy parts and stuff them in, it's a learning experience and this would be part of it. In the future it might be valuable to know what the history of the machine is.
Very good! There is far more information on this website than I could possibly condense in a single post, but you could begin by going through the early postings dating from March 2000 or even earlier.
In your case, your unit is a V1, V2 or V3. However, if it has been refurbished, the BIOS may have been updated to prevent the use of the techniques originally developed here, to downgrade it to a V1 BIOS.
The version numbering is simply a convention that we adopted to easily distinguish between the slight variants that appeared from time to time, as Netpliance tried to shut out the end-users from repurposing (i.e. hacking) the machine for running other OSes and using other ISPs, followed just as quickly by clever reverse engineering by the hackers (in the good sense of the word) here to restore the status quo. It helped to have a common nomenclature to understand what we were talking about.
>I do have an img file for flashing a BIOS, what equipment would I need to do so? Is there a simple programmer I can build to accomplish this? (I have built various eeprom programmers in the past for Atmel chips for very little cost.)
You can flash it in another I-Opener with a V1 BIOS, running DOS & AWDFlash from a hard disk. But this requires hot unplugging and replacing a PLCC chip. Not recommended for a newbie, but should be a piece of cake for you. All usual caveats apply.
> Any speed over 200? or is there a ceiling? Do all the core voltages and multiplers stay the same on those mmx's or do I also need to modify the jumpers?
There are 2 kinds of IOs here: Those without a split-plane supply to the socket (V1, V2, some V3s), and those with (some V3s, V4, V5).
The latter are relatively easy to upgrade with better CPUs (AMD K6-II+/III+/2P, Intel P200 MMX). The core voltages most definitely need modification, and in some cases the FSB speeds and multipliers also.
> I've primarily read about people putting AMD k62+ 450 in there as the preferred chip, is this due to availability or a higher degree of functionality/flexibility?
Combination of availability, functionality and flexibility. It was inexpensive, ran relatively cool, had 128k L2 cache, had terrific performance, and its clock multiplier could be set on the fly by software.