Normally the NVidia GPUs are Palit or Zotac branded, but this is not guaranteed - not sure for AMD though
To know for certain what they currently have in stock you'd have to call them, but when ordering unless you pick one of the brand-specific cards (that are normally a lot more expensive - eg the Asus ROG STRIXs) you can't specify which you brand you want, you get what is next in line.