TANDY/RADIO SHACK
4825 SX
| 
 Processor  | 
 80486SX/80487SX/80486DX/80486DX2  | 
| 
 Processor Speed  | 
 25/33/50(internal)/66(internal)MHz  | 
| 
 Chip Set  | 
 Unidentified  | 
| 
 Video Chip Set  | 
 Unidentified  | 
| 
 Maximum Onboard Memory  | 
 32MB  | 
| 
 Maximum Video Memory  | 
 1MB  | 
| 
 Cache  | 
 None  | 
| 
 BIOS  | 
 Unidentified  | 
| 
 Dimensions  | 
 394mm x 381mm  | 
| 
 I/O Options  | 
 Floppy drive interface, IDE interface, parallel port, PS/2 mouse port, serial ports (2), VGA feature connector, VGA port, riser slot  | 
| 
 NPU Options  | 
 None  | 
| 
 CONNECTIONS  | |||
| 
 Purpose  | 
 Location  | 
 Purpose  | 
 Location  | 
| 
 VGA port  | 
 CN1  | 
 IDE interface  | 
 CN8  | 
| 
 PS/2 mouse port  | 
 CN2  | 
 External battery  | 
 J1  | 
| 
 Parallel port  | 
 CN3  | 
 Speaker  | 
 J2  | 
| 
 Serial port 2  | 
 CN4  | 
 Reset switch  | 
 J3  | 
| 
 Serial port 1  | 
 CN5  | 
 Power LED  | 
 J4  | 
| 
 VGA feature connector  | 
 CN6  | 
 Riser slot  | 
 SL1  | 
| 
 Floppy drive interface  | 
 CN7  | ||
| 
 USER CONFIGURABLE SETTINGS  | |||
| 
 Function  | 
 Label  | 
 Position  | |
| 
 »  | 
 CMOS memory normal operation  | 
 JP1  | 
 Open  | 
| 
 CMOS memory clear  | 
 JP1  | 
 Closed  | |
| 
 »  | 
 Monitor frequency select 31KHz  | 
 SW1/5  | 
 Off  | 
| 
 Monitor frequency select 40KHz  | 
 SW1/5  | 
 On  | |
| 
 »  | 
 Monitor type select color  | 
 SW2/3  | 
 Off  | 
| 
 Monitor type select monochrome  | 
 SW2/3  | 
 On  | |
| 
 DRAM CONFIGURATION  | ||
| 
 Size  | 
 Bank 0  | 
 Bank 1  | 
| 
 4MB  | 
 (4) 1M x 9  | 
 None  | 
| 
 5MB  | 
 (4) 1M x 9  | 
 (4) 256K x 9  | 
| 
 8MB  | 
 (4) 1M x 9  | 
 (4) 1M x 9  | 
| 
 16MB  | 
 (4) 4M x 9  | 
 None  | 
| 
 20MB  | 
 (4) 1M x 9  | 
 (4) 4M x 9  | 
| 
 32MB  | 
 (4) 4M x 9  | 
 (4) 4M x 9  | 
| 
 VIDEO MEMORY CONFIGURATION  | ||
| 
 Size  | 
 Bank 0  | 
 Bank 1  | 
| 
 512KB  | 
 512KB  | 
 None  | 
| 
 1MB  | 
 512KB  | 
 512KB  | 
| 
 Note: The location of banks 0 & 1 are unidentified. The size of the video memory chips are unidentified.  | ||
| 
 VIDEO MEMORY SWITCH CONFIGURATION  | |
| 
 Size  | 
 SW1/6  | 
| 
 512KB  | 
 On  | 
| 
 1MB  | 
 Off  | 
| 
 CPU TYPE SELECTION  | ||
| 
 Type  | 
 SW2/1  | 
 SW2/2  | 
| 
 80486SX  | 
 Off  | 
 Off  | 
| 
 80487SX  | 
 On  | 
 Off  | 
| 
 80486DX  | 
 Off  | 
 Off  | 
| 
 80486DX2  | 
 Off  | 
 Off  | 
| 
 VIDEO RESOLUTION SELECTION (800 X 600)  | |||
| 
 Frequency  | 
 SW1/1  | 
 SW1/2  | |
| » | 
 56Hz  | 
 Off  | 
 Off  | 
| 
 60Hz  | 
 Off  | 
 On  | |
| 
 72Hz  | 
 On  | 
 Off  | |
| 
 56Hz  | 
 On  | 
 On  | |
| 
 VIDEO RESOLUTION SELECTION (1024 X 768)  | |||
| 
 Frequency  | 
 SW1/3  | 
 SW1/4  | |
| » | 
 Interlaced  | 
 Off  | 
 Off  | 
| 
 60HZ non-interlaced  | 
 Off  | 
 On  | |
| 
 70HZ non-interlaced  | 
 On  | 
 Off  | |
| 
 Interlaced  | 
 On  | 
 On  | |
| 
 ON BOARD VIDEO SELECTION  | |||
| 
 Setting  | 
 SW1/7  | 
 SW1/8  | |
| » | 
 Enabled  | 
 On  | 
 Off  | 
| 
 Disabled  | 
 Off  | 
 On  | |