Apple's new iMacs are the high-end desktop computers Mac fans have been waiting for - and they're available now for $1,299 and up

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• One day after refreshing the iPad lineup, Apple has announced a series of spec bumps for the iMac.
• The new 21.5-inch and 27-inch iMacs have faster processors, more RAM, and, perhaps more importantly, AMD graphics cards.
• Now is the best time to buy an iMac if you want a high-performance desktop computer with macOS.

Looks like it's hardware week for Apple. Only one day after the announcement of the new iPad Air and iPad Mini, Apple has taken the wraps off of a new iMac, too. The updates represent a pretty significant spec bump for the iMac, so if you're in the market for a new Apple desktop computer, now is the time to buy.

If you've considered buying an iMac before, you'll be aware of the different models on offer. There's a smaller, 21.5-inch iMac with a 1,080p display and a 21.5-inch iMac with a 4K display. Then there's a 27-inch iMac with a 5K display.

The lower-end, 21.5-inch iMac with a 1,080p display has not been updated, though that doesn't necessarily mean it's not worth buying. It still has a lot to offer for those who want a basic desktop computer with macOS.

However, the 21.5-inch iMac with a 4K display has gotten some pretty major new specs. The base model now comes with a 3.6GHz 8th-gen Intel Core i3 processor, 8GB of RAM, and a 1TB hard drive. It can be upgraded to include up to a 3.2GHz 6-core Intel Core i7 processor, 32GB of RAM, and a 1TB solid-state drive.

Perhaps more importantly, you can get this iMac with an AMD Radeon Pro Vega 20 graphics card, which makes it a much more powerful computer for anyone who needs great graphics processing. Those upgrades will cost you more, though.

The new 27-inch iMac is where power really comes into play, though. The base model has an Intel Core i5 processor with 8GB of RAM and a 1TB Fusion Drive, but it can be upgraded to offer an 8-core Intel Core i9 processor, 64GB of RAM, and up to a 2TB solid-state drive.

You can also get the 27-inch iMac with an AMD Radeon Pro Vega 48 graphics card, which is a workhorse in the graphics world. Naturally, the spec upgrades cost extra, but if you need the extra processing and graphics power, it's worth it.

All-in-all, the new iMac lineup has a lot to offer. Sure, the iMacs didn't get the redesign some people were hoping for, but the iMac is still one of the best-designed, all-in-one computers you can buy, and with these upgrades, the iMac has some of the best specs on the market.

You can buy the new 21.5-inch iMac from Apple for $1,299 or $1,499

You can buy the new 27-inch iMac from Apple for $1,799, $1,999, or $2,299