PCChips probably isn't the brand to go with if you're looking for guaranteed stability. They're a good cheap brand, but not a great brand overall.
Abit has a 645DX board, the SA7. There's really no reason to get a 645 since it limits any upgrade potential (no official 533MHz bus) and the prices aren't that different.
You might want to consider an Intel 845E- or 845G/L-based board if you REALLY want stability but don't need a faster chipset like the 845PE. It'll cost a bit more, but there are reasons PCChips is so cheap (their boards are essentially the same as ECS branded boards). They're not BAD boards, just not great ones.