Google is rolling out Chrome browser version 39 to OS X users. This brings a big change – a shift from 32-bit to full and exclusive 64-bit support.
By switching Chrome to 64-bit, Google hopes that it will be faster and use less memory. The update also patches over 40 vulnerabilities. But there is a drawback – older Macs are stuck on version 38, the last 32-bit version.
Apple announced the switch from PowerPC to Intel COUs in early 2005, with the first hardware making an appearance in early 2006. However, these early Intel Macs were based on 32-bit architecture, and Apple didn't completely adopt 64-bit until August 2007.
Here's when Apple computer models transitioned from 32-bit to 64-bit hardware:
- MacBook Pro: October 2006
- MacBook: November 2006
- iMacs: September 2006
- Mac Mini: August 2007
The MacBook Air was launched with 64-bit processors.
OS X 10.6 Snow Leopard, released in August 2009, was the last OS X release to support 32-bit Intel Macs. Users that are still on that OS release – or earlier – will either have to stick with Chrome 38 and make do with not receiving security patches, or switch to Firefox or Opera, both of which continue to support 32-bit OS X.
Alternatively, it's time to buy a new Mac.
How many people are affected? According to metrics available, some 10 to 15 percent of Macs run Snow Leopard or earlier. It's probably a safe bet to assume that most of these Macs are Intel 32-bit or PowerPC hardware.