Epson Equity 386/33 PLUS User Manual page 72

Slots 1 through 3 are designed for 16-bit option cards and slot 4
is designed for an 8-bit card. As you can see below, a 16-bit
card has an extra connector along the bottom.
M-bit card
Usually it does not matter which slot an option card occupies as
long as the card fits in the slot. For example, you can place
some B-bit cards in a 16-bit slot. However, you must follow
these guidelines when deciding which slot to use:
go into an S-bit slot.
close as possible to the drive it is controlling.
Consult the instructions that come with the card to see if
this is the case.
Note
If you are installing a high-resolution graphics adapter card,
follow the instructions below to install the adapter card; then
see "Using the Alternate VGA Interface" on page 4-16 to
connect the card to the alternate VGA interface in your
computer.
4-12
Installing and Removing Options
8-bit card