Using AutoCAD with Windows 3.1

• Microsoft Windows operating system versions 3.1, 3.11

SUMMARY

This article contains notes on how to use AutoCAD 386 with Windows 3.1 and is divided into the following sections:

• Default PIF Setting Provides Poor Performance
• Running AutoCAD with a UMB Provider
• Running AutoCAD in 386 Enhanced Mode

MORE INFORMATION

Default PIF Setting Provides Poor Performance

The default program information file (PIF) settings for AutoCAD 386 are for a minimum configuration. These settings usually result in poor performance.

The PIF Editor in Windows 3.1 can be used to modify the AutoCAD 386 PIF file settings to optimize the performance of AutoCAD.

Standard Mode PIF Changes

• XMS MEMORY REQUIRED can be set to 1. This forces XMS memory to be provided to an application. (Unless a required amount is given, no XMS memory is provided in standard mode.)
• XMS MEMORY DESIRED can be set between 1024 and 4096. 1024 significantly improves performance. 4096 is the value recommended by the manufacturer for best performance.
• Other Requirements. For these settings to work, you must have adequate XMS memory available. If adequate XMS memory is not available, no adverse effects are noticeable, but performance is only improved by the real amount of XMS provided. You must also have an equivalent amount of disk space free for a swap file.

Running AutoCAD with a UMB Provider

AutoCAD runs in standard mode only if no upper memory block (UMB) manager, such as EMM386.EXE, installed. To run in 386 enhanced mode, upgrade to AutoCAD for Windows.

Running AutoCAD in 386 Enhanced Mode

You must upgrade to AutoCAD for Windows to run in 386 enhanced mode.

AutoCAD is manufactured by Autodesk, a vendor independent of Microsoft; we make no warranty, implied or otherwise, regarding this product's performance or reliability.