Benchmark tests of the early 2011 iMacs released this week were collected by Primate Labs. They show the high-end, 27-inch 3.4Ghz Core i7 model with a Geekbench score of 11602, besting the score of 9124 for the 2.93Ghz model released in mid-2010.
Results are not yet available for all Sandy Bridge iMac configurations, including the 21.7-inch Core i7 iMac. The tests measure processor and memory performance, but do not take into account new video cards or solid-state storage options.
"While the improvements aren't as dramatic as with the Sandy Bridge MacBook Pros, there's a consistent 25% performance improvement between Sandy Bridge and Lynnfield (the previous generation chips) at both the low-end and high-end of the iMac model range," the report said.
The tests also included the iMac models released in late 2009, which were powered by an even older Intel chip line, the Core 2 Duo. The new Sandy Bridge iMacs best those 2009 desktops by about 70 percent in CPU performance, offering what the site said is a "compelling upgrade" for those still running the Wolfdale-based systems.
Apple's new iMacs were released on Tuesday. Apple boasted that the new models are up to 70 percent faster than their predecessors, with graphics performance up to three times that of the previous generation.
Intel's latest-generation Core i processors, dubbed Sandy Bridge has been called by the chipmaker the "biggest advance in computing performance and capabilities over any other previous generations." All of the iMac processors are quad-core, and configurations are available up to a 3.4Ghz Intel Core i7.
The new iMacs also feature AMD Radeon HD graphics, which are not represented in the Geekbench scores. The entry-level 21.5-inch $1,119 model sports the AMD Radeon 6750M GPU with 512MB of GDDR5 memory, while on the high end, custom configurations can feature the Radeon HD 6970M with 2GB of memory.
Promotional materials on Apple's site boast that the new Radeon HD graphics are up to three times faster than their predecessors. They show tests with popular games running on the entry-level 6750M, with "Portal" showing a 4.8 times speed improvement, while "Call of Duty 4" has a 3.5 times boost.