By Kasper Jade

Published: 03:00 PM EST

Amidst pressure from several avenues, Microsoft was forced to cut features from its new Windows emulation software in order to deliver G5 compatibility without further delays.

Many of the feature enhancements originally planned for Virtual PC 7.0 did not make it into the version of software that will begin shipping this month, multiple sources tell AppleInsider.

According to reports, the emerging presence of Apple's G5 processor played a major role in Microsoft's decision to trim a significant number of features from the emulation software late in its development cycle. As a result, sources said that the software may not run as fast as some users may have come to expect.

Native Graphics Card Support

While Apple began introducing G5-based computers in June of last year, a G5 compatible version of Virtual PC had yet to ship a year later. It was about this time that Redmond, Wash.-based Microsoft began feeling pressure from Apple to get the product out the door, sources said. With current and potential G5 customers miffed over a lack of Virtual PC support, and an imminent release of the iMac G5 around the corner, Microsoft began to trim around the fat.

One of the key features to hit the chopping block was native graphics card support. Although Virtual PC 7.0 does deliver faster, cleaner graphics, users will find that the software still emulates the S3 Virge chipset from the late 90s, with no 3D acceleration. Sources said that native graphics support remains under development, but is unlikely to surface for many months.

Expanded RAM and emulated RAM Disk

Several additional features have also been delayed until future revisions of software, such as an increase in the software's PC memory from 512MB to 4GB and a new option to use Virtual PC's virtual PC hard drive as a RAM disk for faster virtual disk performance.

Multiprocessor Support Refinements

Microsoft has also decided to hold off on some refinements to Virtual PC's multiprocessing support, which will eventually allow audio emulation, networking, IDE I/O, and USB functions to be offloaded from the primary processor.

Virtual PC 7.0 was released to manufacturing late last month and should begin arriving on retail store shelves in October. The release will deliver support for G5-based Apple computers, better graphics handling, expanded preferences, and an improved user experience.

Future versions of Virtual PC are expected to reacquire most, if not all of the features cut from the development of Virtual PC 7.0. Unfortunately, sources were unable to provide target release dates, stating only that some features may not mature until next summer.