Recently Apple released its second update to the 15-inch MacBook Pro with Retina display. These Late 2013 MacBook Pros keep the same 2880 by 1800 resolution Retina display as its predecessor, but use the latest quad-core Haswell processors, Iris Pro graphics and PCIe connected flash.

Externally identical to the 4.46 pound, 15-inch models released in February 2013 and June 2012, the changes to this edition of the MacBook Pro are all beneath the aluminum surface. You'll find Intel's fourth generation Core processors (Haswell)--specifcally, a quad-core 2.0GHz Core i7 in the $1999 laptop and a quad-core 2.3GHz Core i7 in the $2599 model. They replace the 2.4GHz and 2.7GHz quad-core Ivy Bridge processors, repsectively, that powered the systems that launched earlier this year. The low-end model ships with 8GB of RAM and 256GB of fast PCIe-connected flash storage. The high-end model doubles both the RAM and storage capacity.

Two Thunderbolt 2 ports replace the Thunderbolt ports on the previous Retina models. Thunderbolt 2 is backwards compatible with Thunderbolt, but you need Thunderbolt 2 devices to see the increased bandwidth.

The rest of the connections remain from previous models: two USB 3.0 ports, HDMI port, SDXC card slot, headphone jack and MagSafe 2 power connector. Wireless connections have been updated to the latest specs: 802.11ac WiFi, which as we've seen in the MacBook Airs, offers much faster wireless transfer rates; and Bluetooth 4.0.

Graphical differences

In a first for Apple, the $1999 15-inch MacBook Pro has no discrete graphics. It relies solely on Intel's Iris Pro (equipped with Crystalwell) integrated graphics. The $2599 model has two graphic cards, the aforementioned integrated Iris Pro as well as Nvidia GeForce GT 750m discrete graphics with 2GB of dedicated video memory.

As our tests of the 13-inch MacBook Pro show, the Iris graphics are considerably faster than the Intel Integrated Graphics 4000 used in the Ivy Bridge MacBook Pros. Unfortunately, the new integrated graphics still have a ways to go before they can match the performance of discrete graphics. In our tests, the Iris Pro graphics in the $1999 MacBook Pro were 33 percent faster than the Iris graphics in the 13-inch MacBook Pro. The discrete graphics in the high-end 15-inch MacBook Pro posted frame rates as much as twice that of the new low-end's Iris Pro.

With the new MacBook Pro, Apple brings the PCIe connected flash storage the company introduced with the mid-2013 MacBook Air. And it's fast. The new low and high-end MacBook Pros were 34 and 41 percent faster, respectively, in our 6GB folder copy test than the high-end early 2013 MacBook Pro and its 512GB SATA-connected flash storage.

Macworld Lab is close to finishing up our new Speedmark 9 overall system performance benchmark, but for now, we're running a dozen application tests to compare performance between Macs. In those tests, the new high-end 15-inch MacBook Pro was faster in eight of our 12 tests and tied in three of the tests. Highlights include a 19 percent higher MathematicaMark 9 scores and 9 percent improvements in Photoshop Creative Cloud and Cinebench R15 OpenGL tests. The previous high-end was 2 percent faster in our 6GB file compression test.

The new low-end 15-inch Retina couldn't keep up with the early-2013 high-end, trailing in 7 of the twelve tests and tying in one. Comparing the new 13-inch Retina MacBook Pro and the new low-end 15-inch model, the 15-inch was considerably faster across the board. The 15-inch's quad-core i7 was about twice as fast in CPU intensive tests like Handbrake, MathematicaMark 9 and Cinebench r15's CPU test, but there were improvements in graphics, storage and productivity applications.

One place where both of the new MacBook Pros shined was in our battery life tests. The new low-end lasted 9 hours and 36 minutes on a single charge. The new high-end lasted 9 hours and 26 minutes, about two hours longer than the early 2013's 7 hour and 30 minute result. The new 13-inch Retina MacBook Pro lasted a little longer: 10 hours and 11 minutes.

Bottom line

Much improved battery life and fast internal storage are both welcome improvements to this latest iteration of the 15-inch Retina MacBook Pro. The $1999 2.0GHz MacBook Pro's lack of discrete graphics took a toll on its Cinebench and 3D game performance, but it's a much faster system than the high-end 13-inch Retina MacBook Pro. The $2599 2.3GHz Retina MacBook Pro was faster in just about every way than the system it replaces and would be a great fit for owners of older Mac portables looking for a high-performance laptop.