I have discovered that the beta3 release installs on a vintage Dell Inspiron 3700! I can’t get internet connectivity though. I can open “network preferences” which shows a list of services but no wifi login is listed with a password (there is a transmitter in the house supplied by the internet provider). Suggestions?
Is your wireless adapter listed, or is there only ethernet one?
I have an old Dell too, on which the wifi adapter doesn’t work.
Can you connect through ethernet?
If you can connect to internet, then you can try to run the script
install-wifi-firmwares.sh
On the terminal to install firmwares for some wireless adapters that requires it.
After booting several times I noticed that changes were not being retained. The install is not fully functioning even when CD install process appears to have been successful. I was fooled by this apparent success! I obviously don’t have a complete install after all.
Be sure to remove install medium from your computer after install. Maybe you are still booting on your DVD.
CD automatically ejects when install is done. I opened the CD drive to double check and there is nothing there. The “pseudo-install” is indeed on the HD.
Can you detail what exactly isn’t retained and what is not functionning?
I do like the fact that Haiku can run on such vintage hardware 
Such an old machine probably did not have a mini PCI or mini PCIe wireless card, it likely uses a PC card (cardbus) wifi adapter, and those are not supported by Haiku. The easiest thing is to use ethernet, you can always get a small ethernet to wifi bridge device.
That era of Dell laptop could be bought with a miniPCI card, but none of the chipsets are likely to have drivers anymore - the Intersil Prism for which the unmaintained driver was recently removed was a common one.
I have a similar-ish era Latitude which has a just about working Intel 2200 transplanted in to it.