as an attempt to make things more convenient for readers I’ve decided to start putting up short descriptions of the various PC ports/slots that can be easily referenced from various posts.
mid/late 90’s computer motherboard
here is a late 90’s PC motherboard. this board is somewhat atypical because it has a lot of at the time obsolete legacy ports and connections but this makes it good for education reasons.
CMOS BATTERY – this particular MB uses a Lithium battery very common in the 90’s and today. it lasts a good while and is not very prone to leakage. very common on MB’s from the mid 90’s up.
IDE – these are IDE connections used on PC’s. these commonly connect to your CD-ROM drive and Hard drive. Newer PC’s use SATA but these started being included commonly on MB’s in the mid 90’s. before that you usually had to buy a separate IDE controller card.
FLOPPY – this is the connector for the floppy disk drives. common on PC’s of all periods, it looks like IDE but smaller
AT – this is where your power supply plugs in, AT is the older standard used pre mid 90’s
ATX – this is where your power supply plugs in, this is the newer standard
AGP – most computers from about 1998 till the late 2000’s have 1 of these slots. usually brown in color. they are exclusively for graphics cards and are faster than PCI or ISA for graphics cards. replaced by PCI-E
PCI – a standard computer slot starting in the mid 90’s and still used as of late 2000’s. usually white in color. used for all variety of cards from audio to video to almost anything else. it replaced ISA.
ISA (16 bit) – a standard computer slot in the 1980’s still found in computers till the late 90’s. usually black in color. used for all variety of expansion cards. slower than PCI which replaced it.
AT KEYBOARD PORT – the port for connecting the computer keyboard on many PC’s from the 80’s till the mid 90’s. replaced by PS/2 ports and then USB.
PS/2 PORT – became the standard port for connecting keyboard and mouse starting in the mid 90’s though it existed well before that.
AT POWER CONNECTOR – the standard power connector untill ATX. used in the 80’s and into the early 90’s
ATX POWER CONNECTOR – the standard power connector from the mid 90’s up. there are some variations that have extra connections especially from about 2005 up.
early 90’s computer motherboard
This is a typical motherboard from the early 90’s. as with the newer board above it has several ISA (16 bit) slots as well as a few others that were completely obsolete by the late 90’s
ISA (8 bit) – an earlier implementation of the ISA standard. standard expansion slot in the 80’s for sound cards, memory cards ect… later ISA (16 bit) is an extension to the 8 bit slot and ISA (8 bit) cards will work fine in 16 bit slots. this slot is smaller and usually black in color like its 16 bit big brother.
VLB – this expansion slot type is directly tied to the 486 cpu so is only found on 486 compatible motherboards and also on some very early Pentium compatible motherboards. this slot is basically another expansion to the ISA slot and is comparable in speed to a PCI slot that later replaced it. it is usually half black with the ending half brown in color.
ancientelectronics 