Pentium III 450

Processor information
Multiplier: 4.5
Default FSB: 100

Stepping: kB0
SL3CC: Retail Boxed
SL364: OEM

Stepping: kC0
SL37C: Retail Boxed
SL35D: OEM

Target speed:
4.5 x 124 = 558MHz

Possible speeds:
4.5 x 112 = 504MHz
4.5 x 129 = 581MHz
4.5 x 133 = 600MHz
4.5 x 138 = 621MHz

The P3-450 has a 4.5 multiplier and a 100MHz FSB. Between the two core steppings, retail and OEM versions, there are four different S-spec numbers. Processors with the most recent kC0 stepping have just started to appear, but we haven't heard anything about the overclockability of these new processors.

As always, start with the target speed or a lower overclocked speed to see if your processor is stable. In the case of the 450, you might want to start at 504MHz (4.5 x 112). You should make sure your system is completely stable at each speed before moving onto a higher setting. Run some strenuous programs or benchmarks for a couple hours. If your system fails to POST or boot Windows, most likely, the processor can't handle the speed, or the AGP video card can't handle the overclocked AGP clock. If the system is able to make it into windows, but crashes after a few minutes, your processor or your AGP video card might be overheating, and you should look into some video or CPU cooling options.

The P3-450 has a good chance at 558MHz (4.5 x 124). The 450 to 558MHz jump is the current overclocking favorite. What, the 24% gain isn't big enough for you? You can also try for 581, 600, or 621, but your motherboard has to support the bus speeds and you better have some fast RAM ready. The 138MHz bus speed looks especially daunting.