PowerBook 3400/200 Speedup
This modification by Joe Vantaggi (joevan@en.com) is based on the work by Robert Marshall (rlmarshall@topher.net). Take a look at PowerBook 3400/180 Speedup. The PB3400c/200 has a 40MHz bus and a 5x multiplier to give the 200MHz machine. The 40MHz bus comes from a silver 40MHz crystal (two pins) located at Y1 on the top of the motherboard, with 40.00T5J on it. It is about 2 inches from the front and about an inch left of the battery bay. It is under the battery charging card; you pull the card and it is located about a half inch forwards from the connector. If you replace this crystal with a faster one, the bus, and thus the processor, speeds up. Here is what we have so far:
| Crystal (MHz) |
Processor (MHz) |
Notes |
| 44.736 |
223.68 |
Everything works |
| 45 |
225 |
Everything works |
| 45.75 |
228.75 |
Everything works |
| 48 |
240 |
Too Fast |
| 49.375 |
246.875 |
Too Fast |
| 49.89 |
249.45 |
Too Fast |