21.5-inch iMac (Late 2013) Review: Iris Pro Driving an Accurate Displayby Anand Lal Shimpi on October 7, 2013 3:28 AM EST
I ran the entry level iMac through our normal OS X CPU test suite. I don't have a ton of Mac desktops in the database but I do have results for last year's 27-inch iMac that'll help put things in perspective. Also keep in mind that the 21.5-inch iMac came equipped with a HDD, while nearly everything else I'm comparing it to has an SSD inside.
Single threaded performance is about on par with an upgraded 13-inch Haswell MacBook Air, which is sort of insane when you think about it. The Core i7 upgrade in the 13-inch MBA can turbo up to 3.3GHz, compared to 3.2GHz with the entry-level iMac’s Core i5. The amount of L3 cache dedicated to a single core is actually the same between both parts (at 4MB). In the case of Cinebench, the 128MB L4 cache doesn’t seem to do much.
Multithreaded performance is obviously much better than what you’d get from a MacBook Air. You’ll notice the entry-level iMac’s performance here is actually quite similar to that of my old 2011 15-inch MacBook Pro. Although the Core i5-4570R has higher IPC and more TDP to work with, since it’s a desktop Core i5 it doesn’t support Hyper Threading and thus is only a 4 core/4 thread part. The Core i7 in my old MBP however is a 4 core/8 thread part, letting it make better use of each core’s execution resources in heavily threaded applications. This is really no fault of Apple’s, but rather a frustrating side effect of Intel’s SKU segmentation strategy.
Looking at our iMovie test we see another 50% advantage comparing last year’s highest end 27-inch iMac configuration to the entry-level 21.5-inch model. The explanation boils down to lower max turbo frequencies and fewer number of simultaneous threads supported. There’s also the fact that I’m testing a HDD equipped system and comparing it to those with SSDs, but most of my OS X CPU test suite ends up being largely CPU bound with minimal impact from IO performance.
iPhoto import performance runs pretty much in line with what we’ve seen thus far. The entry-level iMac is a good performer, but power users will definitely want to push for a faster CPU.
Our Lightroom export test is perhaps the most interesting here. The gap between last year’s 3.4GHz Core i7 and the Crystalwell equipped Core i5-4570R is only 12%. My first thought was to attribute the difference to Crystalwell, but if we look at the gap vs. the 1.7GHz 2013 MacBook Air the iMac’s advantage isn’t really any different than under our iPhoto test. Instead what I believe we’re seeing here is yet another benchmark where Haswell’s architectural advantages shine.
Performance in our Photoshop test is similarly good, with the entry-level iMac coming relatively close (within 20%) to the performance of a high-end 2012 27-inch iMac.
There aren’t any surprises in our FCP-X test either.
I'm slowly amassing results in our Xcode test. What's interesting about the 21.5-inch iMac's performance here is just how inconsistent it was due to the HDD. Subsequent runs either gave me similar performance to what I'm reporting here, or much, much higher build times. If you needed a reason to opt for an SSD, this is a great one. Even looking at the best performance the iMac can deliver, you can see it's not tremendously quicker than the MacBook Air. With an SSD I'd expect to see far better numbers here.
Post Your CommentPlease log in or sign up to comment.
View All Comments
Anand Lal Shimpi - Monday, October 7, 2013 - linkGood call - unfortunately no, Crystalwell isn't reported there either.
Dman23 - Monday, October 7, 2013 - linkGreat review! Thanks for taking the time to review the New iMacs. The Iris Pro 5200 looks extremely interesting.
Guspaz - Monday, October 7, 2013 - linkIt's amusing to me that the 27" iMac is smaller and thinner than my Dell 27" monitor (the U2711), even though the iMac is a full comptuer while my U2711 is just a monitor.
1andrew - Monday, October 7, 2013 - linkThe iMac's have a great display and Target Display Mode is a cool feature. I would really like to see them expand it to non-Thunderbolt/Apple devices. I would love to play my 360 without needing a second display.
twistedgamez - Monday, October 7, 2013 - linkwhy don't reviewers test dota2? i know it's not a particularity intensive game, but lots of people play it (often 10 x number of players of the second game on steam) and lots of people would like to know how it performs, especially when you up the resolution, and lots of people only play dota2 so its not particularly easy to judge its performance when seeing metro/tr performance on lower resolutions
but other than that, a great review!
bluevaping - Monday, October 7, 2013 - linkI know you guys wanted to get a review out, but I think you will see a jump in performance with the upcoming Os X to be released next month. I bet there will be better optimized drivers and support for Open Cl 1.2 and Open GL 4.0
jasonelmore - Monday, October 7, 2013 - link+$250 for nothing but a 128gb ssd for fusion drive is rape.
repoman27 - Monday, October 7, 2013 - linkWell, in the US, it's only a $200 adder. And it's a rather performant PCIe based SSD. Have you priced out an alternative that's as fast or faster for less money? Don't get me wrong, Apple maintains a 36% gross margin which is probably considerably higher than, say, Newegg's, but what were you really expecting for this type of CTO option?
nerd1 - Tuesday, October 8, 2013 - linkYou can get 256 sata3 ssd at much less than 200. They are also charging 200 for extra 8gb of ram.
repoman27 - Wednesday, October 9, 2013 - linkYes, you can get a considerably slower SSD with a crappy controller and lower endurance NAND for less money than Apple's offerings.
The RAM is another matter entirely. It's unfortunate they made it such a hassle to upgrade the RAM yourself in the 21.5" model.