| Manufacturer: | Durango Systems Corporation |
| Type: | Personal business computer |
| Releasedate: | September 1978 |
| Lifespan: | 1978-1984 |
| Media: | two 100 tpi high-capacity 5.25-inch diskette drives storing 480 KB on each single-sided or 960 KB on double-sided diskettes using group-coded recording (GCR) |
| Os: | DX-85M (multi-user/multitasking) |
| Input: | keyboard, full stroke, 84 key |
| Cpu: | 5 MHz Intel 8085A |
| Storage: | 40 MB Shugart SA-4006 14-inch winchester, later 5.25" integrated ST506-interface MFM drive |
| Memory: | 65 KB (up to 196 KB) |
| Display: | 9-inch CRT with 64 characters per row by 16 rows or 80 characters per row by 24, based on the Intel 8275 Video display controller |
| Successor: | Durango "Poppy" |
The Durango F-85 was an early personal computer introduced in September 1978 by Durango Systems Corporation, a company started in 1977 by George E. Comstock, John M. Scandalios and Charles L. Waggoner, all formerly of Diablo Systems. The F-85 could run its own multitasking operating system called DX-85M, which included an integral Indexed Sequential (ISAM) file system and per-task file locking, or alternatively CP/M-80. DX-85M utilized a text configuration file named CONFIG.SYS five years before this filename was used for a similar purpose under MS-DOS/PC DOS 2.0 in 1983.
The F-85 used single-sided 5ΒΌ-inch 100 tpi diskette drives providing 480 KB utilizing a high-density 4/5 group coded encoding. The machine was using a Western Digital FD1781 floppy-disk controller with 77-track Micropolis drives. In later models this was expanded to a double-sided option for 960 KB (946/947 KB formatted) per diskette.
Durango later dropped the "F-85" model name and adopted a user model system, with 700 being the entry model and 950 being the full-featured model.
Still later, they designed a 80186-/80286-based 16-bit system, the Durango "Poppy"; MS-DOS was selected as the entry operating system.