While that's an extensive howto, that aaa has posted for you, just use it as a guide. One good for instance is the mainboard section. That's quite limited. My mobo is by MSI (Taiwanese), and I have no problems with it.
But it's also not mentioned on mandrakes site either!
As far as I have seen, it's net connections and scanners that have "historically" had considerable snags.
The modem for dial up. It seems best to use an external one, judging from the number of posts that I've seen moaning about internal's (mainly discovering that the machines modem is a winmodem - but some of them CAN be made to work).
If you have broadband, then opt for an ethernet type - I've only seen a few problems with them, whereas you search for usb broadband modem problems and you will get screen after screen of posting.
And scanners can be a considerable nuisance whichever way you look at them.
I had lots of probs getting mine working (but managed eventually), then "out of the blue" mandrake release 9.1, and it's all precompiled, detected, etc etc No problems at all.
It also depends on the distro. If you are using one of the "biggies" then as they are updated relatively frequently, hence you get problems solved like my one above.
There is also the option of buying the pc with linux of some kind pre-installed.
Dell (apparently) do one, it can be hassle getting them to supply it, but apparently it's possible. You haven't given a location, but here in the UK, it's either evesham or Mesh that can supply one with mandrake pre-installed - in the US, I'm given to understand that you should even be able to get a linux based PC from Walmart (with lindows, I think).
Hope this gives you some ideas.