When Microsoft announced its Internet Explorer 9 (IE9) in November 2009, it kick-started the push for hardware acceleration by promising that the new browser would boost page content rendering and composition speeds on Windows Vista and Windows XP.

Unlike IE9, , still the most popular version of Windows. It does that by calling on the Direct3D API, which the old operating system supports, rather than Windows Direct2D and Direct3D APIs, which are available only in Vista and Windows 7.

Jacob said that Windows users must have a "very recent driver" if their machine sports an Intel graphics card; version 257.21 or newer for Nvidia cards; and version 10.6 or newer for AMD's ATI-branded cards.

"Unfortunately, certain computer manufacturers do not allow end users to upgrade drivers on their own," said Jacob on Friday. "Hopefully these manufacturers will eventually give their users these much needed graphics driver updates."

Mozilla has of the Intel graphics cards and associated drivers supported by Firefox 4's hardware acceleration.