Custom Built 21.5-inch iMac with Intel Core i9 Outperforms 24-inch M1 iMac in Tests

Despite its impressive performance, the new 24-inch iMac powered by the M1 Apple silicon chip, a new project shows that upgrading a previous-generation 21.5-inch ‌‌iMac‌‌ with an Intel Core i9 processor can deliver similar or even better performance.



The new 24-inch ‌iMac‌ is up to 56% faster than the previous generation 21.5-inch ‌iMac‌ with an Intel processor, which it is replacing. The current highest-end 21.5-inch ‌iMac‌ available features an Intel Core i5 processor, but the desktop computer was previously offered with an Intel Core i7.

Now, taking matters into his own hands, Apple YouTuber Luke Miani, in his latest video, decided to outfit the previous generation 21.5-inch ‌iMac‌ with Intel's latest Core i9 processor. A configuration never offered by Apple officially.

Out of the box, the 21.5-inch ‌iMac‌ featured the Intel Core i3 8100 processor, 8GB of RAM, the Radeon Pro 555X graphics card, and 256GB of SSD storage. Miani himself upgrades the ‌iMac‌ to include the Intel Core i9 9900 and 32GB of RAM. All in all, including the upgrades, the 21.5-inch ‌iMac‌ costs $1,250. In contrast, the baseline 24-inch ‌iMac‌ with 8GB of RAM used in the comparison costs $1,299.

In initial tests focused on graphics, such as Geekbench 5, the ‌M1‌ ‌iMac‌ outperforms the custom 21.5-inch ‌iMac‌ with a score of 7,700, compared to the Intel Core i9 scoring 7,400. In Geekbench tests for computing, the ‌M1‌ ‌iMac‌ scores 20,000 compared to the 21.5-inch ‌‌iMac‌‌ featuring the Radeon Pro 555X, receiving a score of 15,789.

In more computing-centric tests, such as Cinebench, the Intel Core i9 scores 9,214, compared to the roughly 7,500 scores for the ‌M1‌ ‌iMac‌. In a Blender render test, the ‌M1‌ ‌iMac‌ takes around six minutes to render a sample project, while the custom-built 21.5-inch ‌iMac‌ completes the render in three minutes and thirty seconds. It's worth noting, however, that Blender on ‌M1‌ is running through Rosetta emulation, meaning there is a slight drawback in performance.

The full video by Miani is a great watch for those interested in possibly upgrading their own ‌iMac‌ with improved RAM, and a more powerful processor.

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Top Rated Comments

Spanther Avatar
52 months ago
One-off, pimped-out, hand-built Jeep Wrangler Rubicon outperforms factory spec Wrangler Sport in Moab.

News at 11.
Score: 71 Votes (Like | Disagree)
Sebosz Avatar
52 months ago
This brings one interesting thing about these new iMacs - their prices. I know it’s been said many times, but the fact that Apple is offering a 256/8 configuration for $1250 is just absurd. I’ve seen phones with more memory. Or let me put it this way - the money they ask for upgrading these is sick, especially now when nothing in these devices is user-upgradable. It’s just ridiculous.
And before someone says “if you don’t like it don’t buy it” - I’d love to buy one, but I’m not gonna pay 2x more just because I want a 16/1024 configuration.
Score: 54 Votes (Like | Disagree)
macsplusmacs Avatar
52 months ago
This thread is now being drowned out by the noise of the I9's cooling system......
o_O
Score: 45 Votes (Like | Disagree)
fenderbass146 Avatar
52 months ago
okay? Some guy dropped a **** load of money and time to do a mod and it just barely out performs the new entry level
Score: 44 Votes (Like | Disagree)
Andres Cantu Avatar
52 months ago
Lots of salt around the comments. It’s just a project people, not meant to be replicated by the average person who’d just buy the M1.

There’s people out there that appreciate the effort and coolness factor for things like these.
Score: 36 Votes (Like | Disagree)
Rudy69 Avatar
52 months ago

[HEADING=2]Custom Built 21.5-inch iMac with Intel Core i9 Outperforms 24-inch M1 iMac in Tests[/HEADING]
Every single tests in the article was won by the M1 except Cinebench......Who wrote this title?
Score: 30 Votes (Like | Disagree)