Well, the K7S5A was built as a budget board, not an overclocking board. That being said, there are a few overclocking options. You can flash the CheepoBIOS from the forums at
ocworkbench. This will allow you to select FSBs of 133, 143, 146, and 150. There are options for 166 and 200 as well, but these don't work because of a chipset flaw. The board doesn't support voltage changes or multiplier selection, but these can be added on depending on how handy you are with a soldering iron. These mods are available at the same forum linked to above.
You'll want a quality PSU for this motherboard. Specifically it requires a high TCO (total combined output) on the 3.3 and 5 volt rails. My Enermax PSU supplied 180 Watts on these two rails, and that was sufficient for my 1.33 GHz Athlon Thunderbird. The Crucial memory may or may not be a limiting factor. It depends on how old it is, what size it is, and random chance. My fairly new Crucial 256 MB module ran at 225 MHz (450 DDR) when I first got it. Good luck.
In answer to your question, I don't really know how the 2400+ itself overclocks since I don't have personal experience with this cpu.