need good dos diagnostics

what reasonably priced dos diagnostic tools for cpu, memory, ide controller etc do you use?
i have been using a combination of amidiag,and a card from checkit that goes in a pci/isa slot(but can never track down the error codes!).the amidiag tests take a very long time, and have limited batch capabilities.
also, what windows based programs do you use? looking for one that doesn't require an install, but runs from a single directory.
p.s. should be reasonably priced because as you know it will be outdated in 6 months(or less)

disregard this. i posted it twice by mistake.got some great replies. thanks