Sounds like everything you want to do is well beyond what the average person thinks about/is capable of doing. That's okay, but given that it's 18 years past the Intel transition you are highly unlikely to find any products that may have been for sale, for sale now. There's no money in it.
Not really sure what you're going for here, other than the satisfaction of being the bestest, most tricked out Mac PowerPC laptop amongst…MacBook Pros? I say this as a PowerPC fan, but your Mac's best performance would be subpar for later models of Mac laptop. So, there must be some other reason you're wanting to do this (aside from any accolades).
I wouldn't compare any of this with any "MacBook" or any other Intel/AMD/ARM-based junk with all of its associated hardware-level spyware and backdoors. It is completely within reason to seek to beef up your
reliable PowerPC-based hardware if you are going to daily-drive it.
7448 processors, and 7457 for that matter, are not unicorns even to this day, although locating them does trip up a lot of people, because it does take investigating things very patiently to locate them, or devices to desolder them from, or to buy them brand new (are they still manufactured? Back in 2021-ish I know they were).
We don't have a dependency or reliance on "products that are/were for sale" as long as we can get just the processor. We discussed this thoroughly over many years here, and went through great detail about it. We even have a fellow member here from Slovakia,
@JoyBed, who does these upgrades, and does it with a discount if we ship to him also the processor. At least that was the case some years back. (I hope
@JoyBed is doing well today, regardless of whether or not these services are still available.)
Anyway... With all that out of the way, and with all this being said, I do agree that even as a daily-driver, the DLSD's 7447(A? B?) 1.67 GHz processor is really damn good already, and I'd be (rather, am) just happy enough with it, personally.
@NorCalBear I'd recommend just settling with it, and if over the months you are still using your machine that much, like you really mean it, THEN you might want to look into the 7448 step. But I suspect if you get this far, you won't find the need for it.
With a 2.0 GHz 7448 with twice the L2 cache (1 MB vs. 512 KB), it's true everything improves, especially in a sluggish OS like Mac OS X (as opposed to the real Mac OS), but in practice you really notice a benefit with compression/decompression, so if you ZIP/unZIP a lot or similar, which you might if you suck the Macintosh Garden dry with huge compressed ISO downloads all the time, then it's something nice to have. But it's not like the wait time with the stock 7447 will be some unholy trial, so it's fine to just sit and wait. But other than that? Meh, maybe some small speed bump with virtual machines. Slightly smoother HD content. And maybe slightly increase the FPS in ultra-heavy, late OS X games.
About OS 9, that's a nice thought, and a thought in the right direction might I add, but unfortunately the DLSD is the ONLY G4 that we have no record of anyone booting the actual Mac OS with, ever, even in the Mac OS 9 Lives! forums. We do believe it should be possible, if only we knew how to disable devices in the device tree in Open Firmware, and then trying to chop out one device at a time (if anyone knows enough OF to tell us how, that would be very welcome). I wondered if its DDR2 RAM could also be an issue, although developer of Windows NT on PowerMacs mentioned something that suggests if a system can handle DDR1, then it can also handle DDR2 (
here).
However, even if you manage to boot it somehow, do keep expectations in check: It's nowhere near as disastrous as
@Doq worded it, but you'd likely need an external a) USB audio adapter and b) mouse: trackpad would likely move too slowly, but should work, as should the keyboard, because OS 9 has USB drivers, so that should work just fine. Ethernet would also be likely fine, but needs checking. FireWire 400 may or may not work, FireWire 800 would likely work, although at FireWire 400 speeds due to lack of drivers. Likewise, USB 2.0 would work at USB 1.1 speeds. The audio adapter should address audio issues, if any in the first place. WiFi I don't know, but it'd be a real waste not to just use the Gigabit Ethernet port, to say the least. BlueTooth also don't know. (I really couldn't care any less for WiFi/BlueTooth, or rather, if they work, I make it a point to disable them 100% of the time, so when they don't work they just save me the trouble.)
But the ONE issue you'd have for which you have no solution short of writing/porting a driver for it yourself: the GPU. No GPU acceleration. So "video" per se should work perfectly fine, but software that makes use of the GPU simply won't be able to, and instead will behave as if your DLSD had no GPU in it in that regard.
Hopefully that addresses all the points and concerns. Go and get the most out of your awesome PowerBook,
@NorCalBear!
