Might be old Seagate 74 gig SCSI drives, they were common in servers several years ago.
No, they will not simply hook up to your motherboard. You have to have a SCSI RAID controller. If he has the controller card they were plugged into, be sure you get it too. Controller cards are expensive, ($200-$300) for a decent SCSI controller with RAID capability) and if you have to buy one....the old drives are not worth the time or money. You will also need the SCSI ribbon cables.
^+1. SCSI drives can be picky beasts, one reason you never find them in desktop PCs. Installation requires a controller, and there are termination and addressing requirements. Most involve manually setting some jumpers. Get the model numbers and see if Google will find manuals for you.
you can buy scsi raid controllers for dirt cheap on ebay (dell perc4 cards can be found for 30 bux). new they are still somewhat pricy.
also check the connectors on the drive
sca ( 1 big long slot with no separate power connectors) will most likely require a bridge board for each drive to assign the id and provide power and termination capabilities.
68 pin drives should have termination jumpers on them. so all you'll need is the controller and a cable.
id-ing the drive is easy.tart with 0 and work up from there. do no use id 7 as 99% of all scsi controllers use that for thier internal id.
the last drive on the cable farthest away from the controller should be terminated ( by jumper or with a separate termination block) all the rest should not have termination enabled.
if your not using pci-x or pci-e for the raid controller the drives will be fairly slow compared to what you can do with embedded sata raid controllers on most motherboards.
sticking a pci-x controller in a pci slot will work but will be slow.