hsmp:
I've got a G4 Titanium Powerbook at 867mhz and maxed ram at 1gb with original 40gb PATA at 4200rpm drive.
While 867 MHz meets the minimum requirement for Leopard, it just barely does. There is no way to boost the processor speed, but you can improve performance a bit. Maxxing out the RAM is a good move in that direction. The next step is to install a new HDD. Two good reasons for that: 1. The average life of a laptop HDD is 3 to 5 years, which means yours is on borrowed time. As drives age they slow up. The thin coat of lubricant on the platter thickens with age and heat and becomes gummy, spins out to the edge of the platter causing the heads to stick in accessing the drive. In addition, the hydroseal bearings ride in lubricant, which also thickens and breaks down with age. 2. Not only is your HDD 4200 rpm, but it is a mere 40 GB. Getting a larger capacity 5400 rpm GB will not only increase rotational speed, but it will increase the areal density, allowing the heads to read more data on each rotation of the platter, thus speeding up read/write time.
I believe it came with Tiger, but I immediately installed Leopard 10.5.8.
Your computer was originally released with Jaguar (OS X 10.2x), so Leopard is a big jump. As noted, it does meet the minimal procesor speed, but barely.
An SSD may help you boost performance initially, particularly as a boot drive. However, I think your money will be better spent getting a larger capacity HDD. Installing a 160 GB, 250 GB or 320 GB HDD 5400 rpm will make a noticeable difference, and it will cost you less than $100 for the drive, and you can likely install it yourself.
Please do post back if you have further questions.
😉 cornelius