On January 10, 2006, Apple released Mac OS X 10.4.4 with the first generation of Intel-based Macs, the iMac and the MacBook Pro. These machines used Extensible Firmware Interface (EFI) platform firmware instead of the legacy BIOS found on most x86 motherboards. On February 14, 2006, an initial "hack" of Mac OS X v10.4.4 was released on the Internet by a programmer with the pseudonym maxxuss. [14] Within hours Apple released the 10.4.5 update, [15] which was patched again by the same author within two weeks. [16] On April 3, 2006 Apple released their 10.4.6 update [17] and again patches were released within two weeks that allowed users to install most of this update on non-Apple computers, although this did not include the updated kernel in 10.4.6. In June, the hackers released the 10.4.7 Mac OS X update for non-Apple computers using the 10.4.4 kernel.
Up to the release of the 10.4.8 update, all OSx86 patches used the 10.4.4 kernel with the rest of the operating system at version 10.4.8. However, the newer frameworks relied on the newer kernels and this led to users of 10.4.8 encountering many problems. Apple also started making more use of SSE3 instructions on their hardware making it even more difficult for users with CPUs supporting only SSE2 (such as older Pentium 4's) to get a fully compatible system running.
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