ipxe, boot hdt, com32

[robinsmidsrod]

I'm actually quite surprised that those http://memdisk URLs actually boot. Those are invalid URLs, as far as I can tell. URLs are usually built up like this: http://name-of-your-server/path/to/file.html. From what I can tell, I'm guessing that syslinux or iPXE is ignoring that http:// prefix and just treating your URLs as relative paths, in which case I would assume they are being downloaded from TFTP.

Have you turned on logging in your tftp server and web server to see which one is actually serving up your file.

With regards to option number 3, the C32 file might be compiled for another version of syslinux than you are booting with. Where did you get your syslinux binaries from?