honestly ptle5guy--
the 167 mhz mod isnt worth the trouble
u can go out and find a used g4 with the factory 167 bus for less then 50 bucks here
theres one sitting at the shop down the street right now for 40$ from my house
why would i risk messing around with the motherboard when i can just check the classified ads;D
Chris, I would not pay 50 bucks for a motherboard with one resistor less...
I have changed motherboards on PC boxes since 1998... It is only to find a good guide to take off the motherboard from MDDs.
To unsolder SMD components is not easy, but also is not hard if you practice. I have been using a soldering iron to repair my guitar cables since 1990... I am not an expert, but the practice would lead to do it right as Harrymatic says on the post.
It is confirmed that the only difference in motherboards is the dawn R676 resistor. I wish apple would use a jumper, but that is not the case.
Locate and remove the resistor marked R676 on the underside of the board – it’s near the heatsink under the CPU area. (see photos) You’ll need a fine pencil-tip soldering iron. Make sure that the removed resistor doesn’t get lost somewhere on the board! I didn’t find this too difficult as I do a lot of work with electronics, but if you don’t have experience with SMD components, practice loads on some old PCBs first.
Imagine you can get 2 MDD for 50 bucks, one working at 866 and other 1.25 but with the PSU dead. What would you choose? Ah, you would choose BOTH, because you have the money...That is not my case...
Anyway, here in Spain a working MDD still cost 100 Euros (120-130 USA dollars). Even some original Sawtooth are trying to be sold at 100. And MDD PSU also 100. I wish we have those offers here in Europe, but is not the case...
The iFixIt guides for MDD are not deep, but at least we have the best graphic guide I have found for them:
https://www.ifixit.com/Teardown/Powermac+G4+MDD+%28Mirrored+Drive+Doors%29+Teardown/1624It is up to the user if it worth to pull out the motherboard from the box. Eventually, if you buy a MDD 166 bus motherboard, you will have to pull out the old-slow motherboard...
Please, if someone swap out a MDD 133 board, and have no interest on it, PM me. I would pay shipping cost in Europe.