433DX/450DX2/466DX2 (259-7715/16/17)  Jumper Settings  Faxback Doc. # 2682
OMNI II MID TOWER

The following tables show the settings for jumper blocks on the main logic
board.  A hyphen between pin numbers indicates that a jumper should be
installed to connect those pins.  For example, "1-2" indicates that a
jumper should be installed on Pins 1 and 2.

NOTE:  Jumper settings not mentioned in the following table are not usually
       needed to be changed by the user, and should be left in their
       factory default positions.

USER-SET JUMPER BLOCKS

The following table shows jumper settings that you might need to change.
See the referenced sections for details.

┌──────┬────────────────────┬─────────────┬──────────────────────────────┐
│JUMPER│  FUNCTION          │ OPTION      │ JUMPER SETTING               │
├──────┼────────────────────┼─────────────┼──────────────────────────────┤
│ W6   │Enables or disables │Enable*      │ Not installed                │
│      │BIOS for on-board   ├─────────────┼──────────────────────────────┤
│      │video**             │Disable      │ Installed                    │
├──────┼────────────────────┼─────────────┼ ─────────────────────────────┤
│ W11  │ Enables or disables│Enable*      │ 1-2                          │
│      │ on-board video**   ├─────────────┼──────────────────────────────┤
│      │                    │Disable      │ 2-3                          │
├──────┼────────────────────┼─────────────┼──────────────────────────────┤
│ W8   │ Clears CMOS RAM    │Do not Clear*│ Not installed                │
│      │ and power-on pass- ├─────────────┼──────────────────────────────┤
│      │ word***            │Clear        │ Installed for 2              │
│      │                    │             │ seconds and then removed     │
├──────┼────────────────────┼─────────────┼──────────────────────────────┤
│ W4   │Enables or disables │ Enable      │ 2-3                          │
│      │diskette drive      ├─────────────┼──────────────────────────────┤
│      │write protection****│ Disable*    │ 1-2                          │
├──────┼────────────────────┼─────────────┼──────────────────────────────┤
│ W12  │ Sets video memory  │ 50 ns*      │ W12: Installed               │
│ W13  │ speed to match the │             │                              │
│ W14  │ slowest video      │             │ W13: Installed               │
│      │ memory installed   │             │                              │
│      │ *****              │             │ W14: Installed               │
│      │                    ├─────────────┼──────────────────────────────┤
│      │                    │ 60 ns       │ W12: Not installed           │
│      │                    │             │                              │
│      │                    │             │ W13: Not installed           │
│      │                    │             │                              │
│      │                    │             │ W14: Not installed           │
│      │                    ├─────────────┼──────────────────────────────┤
│      │                    │ 70 ns       │ W12: Installed               │
│      │                    │             │                              │
│      │                    │             │ W13: Installed               │
│      │                    │             │                              │
│      │                    │             │ W14: Not installed           │
├──────┴────────────────────┴─────────────┴──────────────────────────────┤
│*     Indicated factory setting..                                       │
│**    See "Installing an 8514/A-Compatible adapter" in the "Video"      │
│      section.                                                          │
│***   See "Clearing the power-on Password" in the "System Security"     │
│      section.                                                          │
│****  See "Write Protecting the Diskette Drive" in the "System Security │
│      section.                                                          │
│***** See "Installing Video Memory" in the "Upgrading Main Logic Board  │
│      Components section.                                               │
└────────────────────────────────────────────────────────────────────────┘

FACTORY-RESERVED JUMPER BLOCKS

The following jumper blocks are reserved for factory use.  Do not change
the settings for these jumper blocks:
┌──────────┬────────────────────────┬────────────────────┬───────────────┐
│  JUMPER  │   FUNCTION             │ OPTION             │ JUMPER SETTING│
├──────────┼────────────────────────┼────────────────────┼───────────────┤
│  W3      │   Sets mircroprocessor │ 25MHz and 50MHz    │ Installed     │
│          │   speed                ├────────────────────┼───────────────┤
│          │                        │ 33MHz and 66MHz    │ Not Installed │
├──────────┼────────────────────────┼────────────────────┼───────────────┤
│  W19     │   Enables or disables  │ Enable             │ Installed     │
│          │   video IRQ9           ├────────────────────┼───────────────┤
│          │                        │ Disable*           │ Not Installed │
├──────────┼────────────────────────┼────────────────────┼───────────────┤
│  W20     │   Reserved for future  │ Standard Setting*  │ 1-2           │
│          │   use                  ├────────────────────┼───────────────┤
│          │                        │ Not applicable     │ 2-3           │
├──────────┴────────────────────────┴────────────────────┴───────────────┤
│  *Indicates factory setting.                                           │
└────────────────────────────────────────────────────────────────────────┘

(smc/tmc-071/29/95)