You need data files from original Doom 3 version 1.3.1 (NOT BFG
edition):

  MD5 (base/pak000.pk4) = 71b8d37b2444d3d86a36fd61783844fe
  MD5 (base/pak001.pk4) = 4bc4f3ba04ec2b4f4837be40e840a3c1
  MD5 (base/pak002.pk4) = fa84069e9642ad9aa4b49624150cc345
  MD5 (base/pak003.pk4) = f22d8464997924e4913e467e7d62d5fe
  MD5 (base/pak004.pk4) = 38561a3c73f93f2e6fd31abf1d4e9102
  MD5 (base/pak005.pk4) = 2afd4ece27d36393b7538d55a345b90d
  MD5 (base/pak006.pk4) = a6e7003fa9dcc75073dc02b56399b370
  MD5 (base/pak007.pk4) = 6319f086f930ec1618ab09b4c20c268c
  MD5 (base/pak008.pk4) = 28750b7841de9453eb335bad6841a2a5

Please place them under %%DATADIR%%/base.

Optionally, you can also use Resurrection of Evil expansion pack
files:

  MD5 (d3xp/pak000.pk4) = a883fef0fd10aadeb73d34c462ff865d
  MD5 (d3xp/pak001.pk4) = 06fc9be965e345587064056bf22236d2

These should be placed under %%DATADIR%%/d3xp

Please consult https://github.com/dhewm/dhewm3/wiki/FAQ for more
info.