We have a drill machine that has an old type of pc buried in it. When it boots up the Bios now can't find the Hard disk. Luckily we took a copy of the HD a few years back. The problem is the Bios is so old that it has the old Type 1 - 46 HD or 47 for a user defined ( which the current HD is ). It's going to be very tricky to find an 83mb replacement hard disk and as only understand the basic's of this type of bios what is the maximum hard disk I'll be able to install in there and it still recognise it (trying to increase my buying scope for a 'new' HD ).