Electronics modification is in no way my specialty, so, unfortunately, some things are a mystery to me. In particular, resistors.

Electronics, being precise and carefully designed things, require precise and careful work. Obviously, you can't just throw any old part into any situation.

With resistors, they can have the same ohm ratings, but different watt ratings. And, what about their physical size? The resistors in a mini are a lot smaller than the resistors in a beige G3. How are you ever supposed to know which kind to use?

You could measure them, I suppose, with some sort of tool. I don't have anything like that, and last time I saw a tool for checking wires or signals (this was for checking ethernet cables), it was rather expensive.

I'm writing this because, as some of you know, I'm in the slow process of scrounging up money and parts to work on an PowerMac G4 (Mirror Drive Door). In order to change the clock speed, I need to move around (and, as a result, add) resistors to the motherboard. I haven't yet taken the thing apart to see how big they are. All I know is that they're 1k ohm. I don't know their wattage.

Or... Does the wattage determine its actual size? Are bigger resistors higher wattage resistors? Is a 1/8 watt resistor like the size of an ant?

Some people have also said you can bypass soldering by drawing in new lines on the motherboard with something like a defroster line pen for car windows. But, much as I don't know how to tell exactly what kind of resistors I need, I have no idea where to draw the lines! (Would you draw the line to bypass the spot where a resistor goes in, or do you cake the stuff on in place of a resistor?)

Anyway, maybe responses to this thread can help out some newbies like myself. And, maybe some day I'll make shorter posts... Nah.

As with most things I ask questions about, I find the answers shortly after.

Though I still think it'd be beneficial for some vets of all of this to reply, here's what I've learned.

Resistors not only come in different ohm/watt ratings, but different sizes and types. My assumption is that most Macs are using those surface mount resistors (SMD resistors?). I've also learned, thanks to the nice resistor article on Wikipedia, how to identify certain qualities of resistors.

In my own case, I'm just going to have to take apart some of my Mac and see what kind I need.

Here's the Wikiepdia article (en.wikipedia.org/wiki/Resistors) - Enjoy!

They are indeed surface mount resistors in the vast majority of modern Macs.

There is really no need to replace resistors on cpu mods. Using a defroster pen has the same resistance as does solder or even a graphite pencil! I havent seen any of them not work if used correctly. I recommend the pen myself as soldering the damn things back on can be very difficult.

Resistace is FUTILE!!!

wow sorry about that.

:S