Latest Puppy - failed to boot on a Compaq Presaio 2100 laptop (AMD Athalon 2800+, 512Mb). It got as far as warning that it wouldn't write pup001, let me hit return, then the fan started racing, and that was all she wrote.
This isn't a big deal to me and I don't expect to expend any energy working out what went wrong. But it might be a useful data point for someone.