System Board Type 8639 (FRUs 60H7198 / 11H5545)
System Board Type 8639 (FRUs 60H7198 / 11H5545)
1 Riser Connector
2 Modem Ring Detect jumper (MRD)
3 Diskette Drive write protect jumper (WP) (J29)
(Pin 1-2 normal operation (default))
(Pin 2-3 read only)
4 Diskette Drive Connector
5 Hard Disk Drive Connectors
0=Primary 1=Secondary IDE - Drive
6 On/Off Switch Power Connector (J38)
7 On/Off Switch Connector (J37)
8 Power Supply Connectors
9 Bus/CPU Speed MHz (J26/J27)
10 256KB/1MB Cache Jumpers (J21 J22 J23 J24)
Cache J21 J22 J23 J24
----------------------------------
256KB 1-2 1-2 1-2 1-2
512KB 1-2 1-2 2-3 2-3
1MB 2-3 2-3 2-3 2-3
11 Processor Socket
12 Microprocessor Ratio (J101)
Example:
90 MHz processor and bus speed is 60 MHz
set the jumper to bus-to-core ratio to
60/90 = 2/3.
(bus-to-core ratio 1/2 = jumper conn.)
(bus-to-core ratio 2/3 = no jumper)
If the ratio is incorrect.. component
can OVER-HEAT and DAMAGE can occur !
13 Cache Connectors
14 Memory Connectors (Bank 2)
15 Memory Connectors (Bank 1)
16 Memory Connectors (Bank 3)
17 Video Memory Modules
18 Power-ON Password jumper (PWD) (J40)
19 Battery
20 Display Connector
21 Parallel Connector
22 Serial Connector
23 Serial Connector
24 Keyboard Connector
25 Mouse Connector
26 Audio (input jack)
27 Audio (output jack)
28 IDE CD-ROM Audio Connector
29 Mouse jumper (J28)
(The following items may not be present, on 8639 System Boards)
30 Hard Disk (1-2) / Power LED (3-4)
(If an Adaptec PCI-SCSI AHA-2940 / SCSI-HDs are installed
then the HD-LED should be connected to the Adaptec SCSI
controller board.) >> Adaptec SCSI adapters
31 Fan
32 FT-PNL (Audio)
33 Speaker (3-4)
35 Mute (Audio)
36 VIDEO Feature Connector
Jumper Settings
| Jumper |
Setting |
Description |
| MRD |
2-3 (D) |
Modem answer to ring |
| MRD |
1-2 |
Modem no answer to ring |
| WP |
2-3 (D) |
Enable writing to diskette |
| WP |
1-2 |
Disable writing to diskette |
| J101 |
1-2 (D) |
2/3 Bus/Core Ratio |
| J101 |
2-3 |
1/2 Bus/Core Ratio |
| PWD |
1-2 (D) |
Password enabled |
| PWD |
2-3 |
Password reset |
BUS / CPU - Speed select (J26 / J27)
All CPU SPEEDs and CACHE sizes may NOT BE AVAILABLE
| Jumper |
50/75 MHz |
60/90 MHz
60/120 MHz |
66/100 MHz
66/133 MHz |
| J26 |
2-3 |
2-3 |
1-2 |
| J27 |
2-3 |
1-2 |
1-2 |
Memory Table (Preferred Combinations)
Each Bank MUST contain a MATCHED PAIR having the same SIZE & SPEED
| TOTAL MEMORY |
BANK-1
MEM 1 / 2 |
BANK-2
MEM 3 / 4 |
BANK-3
MEM 5 / 6 |
| 8MB |
4MB |
--- |
--- |
| 16MB |
4MB |
4MB |
--- |
| 16MB |
8MB |
--- |
--- |
| 24MB |
4MB |
4MB |
4MB |
| 32MB |
8MB |
8MB |
--- |
| 40MB |
8MB |
8MB |
4MB |
| 48MB |
8MB |
8MB |
8MB |
| 64MB |
16MB |
16MB |
--- |
| 72B |
16MB |
16MB |
4MB |
| 128MB |
32MB |
32MB |
--- |
| 136MB |
32MB |
32MB |
4MB |
| 192MB |
32MB |
32MB |
32MB |
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