All Macs In-Depth Tests

Yosemite Overclock to 400Mhz and Above - Is It Possible Through Simple Surgery ?

We got an email from Roger Vass the other day. He went to the recent Macworld in San Francisco harboring the suspicion that each of the new Yosemite machines have different jumpers that determine if they are 300Mhz, 350Mhz or 400Mhz. Stopping by the Apple booth displaying the new machines he examined an open Yosemite 400Mhz G3s motherboard and noticed that there was a long white jumper next to the G3 Zif processor (see picture).

The jumper was labeled with the following "breaking label voids warranty." He asked a loitering Apple engineer about this and was told the jumper was for overclocking the CPU. He was told that you can take the jumper from the 400Mhz machine and put it into a 300Mhz one and overclock that to 400Mhz. Speculation: would it be possible to overclock it to a higher speed with a different jumper? Anyone who has any details about this please email us and we will publish further information.

Yosemite Pins/Speed

The pin setting information below was gleaned from a legitimate source on the Web. We do not know what the practical effect of changing the jumper settings would be on performance, but we would love to find out. Use the information below cautiously and at your own risk.

The first 4 pins of the Yosemite Jumper Block should be as follows:

MHz P1 P2 P3 P4
300 J