[ShortcutToMoncton]

The parents-in-law's Windows machine just crapped out and I was thinking of getting them a used Mac (English is not their first language and they have a problem clicking on some of the especially tricky email viruses - their old machine inevitably needed a wipe at least twice a year). They basically don't do anything on it besides web surfing/email and some very rare AutoCADing.

I see some good value with the 2009-era iMacs with 27" screens - 2.8 Ghz i7 processors, albeit with 1067MHz DDR3. 512Mb Radeon 4850 cards definitely won't be speedy but I would imagine just as good as the built-in Intel graphics in Minis and iMacs that are several years newer?

And do you foresee any issues with El Capitan with a Mac that old?

[P]

The first 27" iMacs, at least the quadcore models, remain speedy - I still have one such as my main Mac, and my plan is to switch when there is a 13" MBP that matches it. That still hasn't happened.

Radeon 4850 is still decent, and I have never seen slowdowns of the type that I can sometimes see on the MBA or older iMacs. It's even still possible to game seriously on it, if one drops the resolution to 1280*720 (so each virtual pixel becomes 4 real ones exactly) for shooters. No graphics bugs the way Intel graphics sometimes have in games. The one worry I have about the graphics is that Apple doesn't support OpenGL 4 on them, which might, at some point, be an issue. It isn't yet, it might never be (or at least, not before lack of Metal/Vulkan support becomes an issue, which would also affect much newer machines) but I figure I should mention it.

Other notable hardware limitations are few and far between, actually. There is no AES-NI in the CPU, so full disk FileVault will mean a slowdown. Having four cores should cover that, though. No video acceleration on the GPU due to lack of Apple drivers for it, but again, having lots of cores means that that is no issue. Max RAM is 16GB, DDR3-1333 is supported. It is possible to install an SSD in the optical slot, though the operation is quite tricky. HDD upgrade is not recommended as you need to match the type to make the heat sensor work. i7 or i5 makes absolutely no difference (I have the i7), so if you get a good deal on the i5, get that.

[ShortcutToMoncton]

Awesome - many thanks! So you don't think there's much of a difference between i5 or i7? I always thought the i7 was supposed to be much better?

[reader50]

The early 27s (core i5 or i7) handle 32 GB, even though Apple says 16 GB. Only the Core 2 Duo / Core i3 models are limited to 16 GB.

[P]

Originally Posted by ShortcutToMoncton 

Awesome - many thanks! So you don't think there's much of a difference between i5 or i7? I always thought the i7 was supposed to be much better?

The differences between the i5 and the i7 are:

* 133 MHz higher clock and another 133 MHz higher turbo
* Hyperthreading
* various minor features that Intel locked out, like VT-d

133 MHz higher clock doesn't hurt, but it is a few percent more for usually a lot more money. Hyperthreading is the one that is intended as the big draw, as it can be as much as 30% more performance in the right circumstances, but it does absolutely nothing until you're trying to run more than 4 threads at once. Having used that machine for years, I can state that that is extremely rare. Hyperthreading on a dual core kicks in when you try to run more than 2 threads, which happens much more often, so it makes sense there, but on a quad - don't bother.

The "various minor features" are not things that any regular user will use. I mention it only because it was the reason I picked the i7 - I wanted VT-d. (VT-d means that you can dedicate any PCI device, like the GPU, to a virtual machine - I hoped that that would make it possible to game at full performance in a Windows VM some day. That never happened.)

[P]

Originally Posted by reader50 

The early 27s (core i5 or i7) handle 32 GB, even though Apple says 16 GB. Only the Core 2 Duo / Core i3 models are limited to 16 GB.

Really? Because Intel reports a 16GB ceiling on those CPUs, and they usually don't lowball their estimates the way Apple does.

[reader50]

Mactracker reports 32 GB for the i5 / i7 models. Everymac has greater detail - page for the 27 core i5 (late 2009).

*Officially, this model supports a maximum of 16 GB of RAM. However, as carefully confirmed by Other World Computing, this model can support up to 32 GB of RAM if it is running Mac OS X 10.6.3 "Snow Leopard" or higher in 64-bit mode and has been updated to use the latest EFI version. It is limited to 16 GB of RAM in 32-bit mode.

[P]

Interesting. Not that I need more than the 16GB I have, but still.