Colin Weber asked: >We have a requirement to re-design an existing ISA bus card design onto a >5V, 32-bit PCI card. > >1. >First glance at PCI specifications highlight that there are two default >sizes for these cards, Short and Long. What is the reasoning behind this? There are many types of card cage configurations in PC's and some of them have slots which can only accomodate a half length format. The PCI local bus Specification rev 2.1 says "The fixed and variable height short length cards were chosen for panel optimization to provide the lowest cost for a function". I'd say the PC people have gotten wise to the idea that they should get a smaller board for less money, and that the number and size of components necessary to make an ethernet NIC, for instance, has dropped to 12-15 square inches. In short, cost. >Or another way of asking the same question, can the length of the board be >vary? Yes. The length has a lower limit of about 12 cm from the faceplate edge to the end of the finger connector. I have seen boards which have irregular shapes in which the connector edge is a couple inches longer than the opposite edge, and they are panelized to yield more units. >Does it have to conform to either of the specific short or long lengths? Our Company is definitely producing NIC's (network interface cards) shorter than the 6.875" "short card", and so are many others. I'd recommend that you go out and buy some products and take a look at the configurations. Your local CompUSA should have numerous brands to choose from. I know that Intel (who is godfather of the PCI bus) has some NIC's with very clever small and irregular layouts. Both lenght and height are varied in many of these. See: http://www.pcisig.com/ good luck, Jerry Cupples Interphase Corporation Dallas, TX USA http://www.iphase.com ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################