 Acer File Extensions |
Advent 425SX PC
| CPU | Intel 80486SX AT compatible Running @ 25Mhz in the 19 x 19 pin LIF socket |
| BIOS | ACER/IBM System BIOS. (Flash Eprom) ver 66V1.21. Date: 21/10/93 |
| Memory | 4MB in SIMM Slot 1 of 2. Upgradeable to 32MB using 2 x 72 Pin SIMM Cards of 70 nanoseconds or faster |
| Cache | 8KB internal cache on 80486SX chip. External cache option supports 256Kb of memory - 20ns |
| Hard Drive | 170MB |
| CD Drive | Not Fitted |
| Video Card | Cirrus Logic CL-GD5422/GD5424 - 512KB |
| Sound Card | Not Fitted |
| Keyboard | 102 IBM PC-AT Compatible |
| Mouse | IBM PS/2 Microsoft compatible |
| Interfaces | 1x Parallel port, 25 Pin. (IRQ 7) 2x 9 Pin Serial ports 1x Keyboard Interface PS2 1x Mouse port PS2 (IRQ 12) |
| Expansion | 3x AT/ISA compatible (16 Bit) slots |
Motherboard Information
CPU
CPU Selection
| Speed | JP7 | JP8 | JP9 | JP10 | JP17 |
|---|---|---|---|---|---|
| 25MHz (DX250) | 2-3 | 2-3 | 1-2 | 2-3 | 2-3 |
| 33MHz (DX266) | 1-2 | 2-3 | 1-2 | 2-3 | 2-3 |
| 40MHz | 1-2 | 1-2 | 2-3 | 1-2 | 1-2 |
| 50MHz | 2-3 | 2-3 | 1-2 | 1-2 | 1-2 |
| Type | JP11 | JP12 | JP13 | JP15 | JP18 | JP20 | JP27 |
|---|---|---|---|---|---|---|---|
| 486 | 1-2 | 1-2 | 1-2 | 1-2 | 2-3 | 2-3 | Off |
| P24T | 1-2 | 2-3 | 1-2 | 2-3 | 1-2 | 2-3 | Off |
NB: IBM do not recommend use of a DX4 chip.
Memory
4MB non-parity (parity chips may be fitted but then the non parity memory will not be recognized) as standard in 1 of the 2 SIMM slots. (Some machines may come with the memory hardwired to the motherboard in the middle of the SIMM slots). 2 x 72 PIN SIMM slots available, (1 occupied).
An unusual feature of this machine is the ability to accept a mix of differing memory chips to give various memory configurations.
In the Box
Documentation Supplied
- Advent User's Guide Manual
- Microsoft Windows 3.1 User's Guide
- PC-DOS 6.1 Registration card
- PC-DOS 6.1 Disc Compression Function Order Form
- PC-DOS 6.1 User's Guide
- PC-DOS 6.1 Keyboard and Code Pages Guide
- Special Offers for PC-DOS 6.1 Customers
Known Issues
Forgotten Password
Switch off machine, remove lithium CMOS battery and leave for 30mins. Replace battery and restart machine.
The User Manual refers to using a utility called CLMODE to optimise the video configuration
This utility is not currently supplied with the machines, but may be supplied on future machines.
When setting either a Setup password or Power-On password, and restarting the machine, it simply goes into Windows as per usual
Move jumper postition JP2 (labelled PSSWRD) to the 1-2 position. This is located next to the battery and close to the power supply unit.
Cannot get cache to work
The best setup is a 256k one. You need to change 3 jumpers - JP24 JP25 and JP26 - JP24=CLOSED, JP25=CLOSED, JP26=CLOSED between 2 and 3. The cache speed is 20ns and will fill both banks chips U56 to U63