On your 1st link: the 3rd CF2IDE is fine, as a bonus it allows you to set it as either master or slave, but in a nutshell the 2nd could do as well, the 1st one? Not so much. I'm not even remotely sure it's a CF converter, but given CF cards are "similar" to IDE... If your mobo or controller has two IDE channels, then you're better off with a DOM (Disk-on-Module), which plugs directly into the IDE port, so you can spare the 2nd one for either a CD drive or another disk.

As for the POST card, the cheapest one will do... Just be sure that it comes with a manual explaining what the codes mean for each bios...

That first one looks like 40 to 44-pin. Not sure what the top connector would be for.

As for the CF adapter: buy the one that fits best. I mainly use the DOM-style ones (third in your gallery).

As for debugger cards, they are all equal. As long as they show POST code and voltages, you can't do wrong.

21603 wrote:

That first one looks like 40 to 44-pin. Not sure what the top connector would be for.

Here is another photo of it:

https://i.imgur.com/e9PUVTN.jpg

Looks like it's a combo 44-pin IDE or CF -> IDE adapter.