In addition, Direct3D is WHQL certified on a _wide_ range of graphics HW, meaning workstation, consumer, game, laptop, and integrated-on-the-otherboard graphics chipsets. Essentially, using Direct3D, the only differentiator is performance. This is not true with OpenGL, where OpenGL graphics drivers actually _disable_ some OpenGL functionality on consumer, game, laptop, and chipset HW so you are _forced_ to purchase the more expensive workstation graphics HW, just so your OpenGL graphics works correctly.
Ultimately, we want to provide an Inventor product that is of the highest quality in terms of graphics _and_that is affordable for a _wide_ range of budgets. For example, if you are no longer _required_ to spend $1000 to $2000 to simply have graphics HW that works, but can instead purchase a $100 to $350 game card ... then you can take the $900 to $1650 you saved and spend it on other system aspects that might have a _much_ more significant impact on your user experience with Inventor, such as having 8 GB of RAM instead of 4 GB (a _real_ 64-bit system!), having high performance Ultra SCSI SAS drives instead of SATA, or having top-of-the-line multi-core CPU(s) instead of a single lower cost CPU version. Or ... alternatively, if you so desire, you can purchase a lower-cost system in order to save some money and Inventor will actually work on it from a graphics point of view. Any student budget should allow you to purchase a low cost laptop that will work with Inventor becasue if you can play a Direct3D game, you can run Inventor, so far as the graphics are concerned.
Al