installing Windows on an iMac without OSX

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MikeB4

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#162047 27-Jan-2015 18:41

Wasn't sure if this should be here or under Windows, Mods please feel free to move if needed.

I want to install Windows 8.1 on my 2011 27" iMac. I want to have Windows without OSX so not Bootcamp or VM. Has anyone here done this if so what process used and how did it work out.

Thanks in advance.

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#1223510 27-Jan-2015 20:12

Just picked up a 2010 version yesterday and googled the same question. No immediate success. I have a suspicion that something BIOS-related prevents it.

I've ordered a Western Digital Dual Drive to put in mine. Bit of a PITA to install the drive, but the result should please the Mrs who is displeased with multiple drive letters on our current home computer (an USDT with a 27" ultra-wide LCD and separate SSD and HDD). Would be annoying to have a few % of the drive taken up by MacOS.

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sdavisnz

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#1223530 27-Jan-2015 20:17

best thing to do would be give os like 20gb of hard disk space and bootcamp the rest.

you can set windows to be the default boot option so you wont ever se osx unless you wanted to.

- thats what i would do atleast

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Dynamic

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#1223531 27-Jan-2015 20:20

sdavisnz: best thing to do would be give os like 20gb of hard disk space and bootcamp the rest.

You are most likely right. Just don't be too stingy on the OSX partition I think, as if you have Win7 or Win8 installed and want to install Win10 instead but that requires a newer version of Bootcamp which requires a free upgrade to OSX Yosemite+1 which requires X disk space to install.... you know the drill!

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MikeB4

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#1223533 27-Jan-2015 20:22

Yeah the EFI no doubt will have restrictions

MikeB4

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#1223538 27-Jan-2015 20:26

I am hoping to avoid Boot camp as it has overheads that degrades performance

Mark

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#1223548 27-Jan-2015 20:30

KiwiNZ: I am hoping to avoid Boot camp as it has overheads that degrades performance

No it doesn't.

This thread explains what it is and isn not quite nicely.

sdavisnz

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#1223552 27-Jan-2015 20:32

Mark:
KiwiNZ: I am hoping to avoid Boot camp as it has overheads that degrades performance

No it doesn't.

This thread explains what it is and isn not quite nicely.

agree - the whole point of bootcamp is to get the full potential out of the mac = no overheads

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MikeB4

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#1223555 27-Jan-2015 20:33

Mark:
KiwiNZ: I am hoping to avoid Boot camp as it has overheads that degrades performance

No it doesn't.

This thread explains what it is and isn not quite nicely.

Thanks for that link I shall have a read. I have done Boot camp installs several times but it always hindered.

alexx

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#1223564 27-Jan-2015 20:42

From my understanding it is possible to install recent versions of Windows in EFI mode with some of the newer Macbook Air and other recent models, but not with some older models. It seems to depend on the Firmware. If not supported, then you need Bootcamp and that means you need to install via OS X with Windows installed in BIOS emulation mode (some people have succeeded in leaving just the running Windows system without OS X system).

Of course you still need the OS X installation if you want firmware updates as these are delivered via OS X sw updates / app store. This includes the firmware update to patch the recent Thunderstrike vulnerability. You could run OS X from USB just for testing and firmware updates.

#include <standard.disclaimer>

gehenna

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#1223577 27-Jan-2015 20:59

Not possible. You can mess with the sorts of OS's you can install but you still need OS X on there somewhere. rEFIt will let you customise the number of partitions and provide a boot menu.

Regardless, you still need the drivers that BootCamp installs to make proper use of the Mac hardware.

There is no overhead on Windows if using BootCamp. You might be thinking of the overhead involved in virtualising Windows on a Mac using Parallels, VMware Fusion, or VirtualBox.

MikeB4

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#1223581 27-Jan-2015 21:08

gehenna: Not possible. You can mess with the sorts of OS's you can install but you still need OS X on there somewhere. rEFIt will let you customise the number of partitions and provide a boot menu.

Regardless, you still need the drivers that BootCamp installs to make proper use of the Mac hardware.

There is no overhead on Windows if using BootCamp. You might be thinking of the overhead involved in virtualising Windows on a Mac using Parallels, VMware Fusion, or VirtualBox.

Thanks for that, sad now. Oh well I shall try Boot camp again.

gzt

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#1223584 27-Jan-2015 21:13

KiwiNZ: I am hoping to avoid Boot camp as it has overheads that degrades performance

Some macs shipped with a not impressive level of memory for the windows world. Imo osx base was fine with this for obvious reasons ; )

MikeB4

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#1223598 27-Jan-2015 21:19

gzt:
KiwiNZ: I am hoping to avoid Boot camp as it has overheads that degrades performance

Some macs shipped with a not impressive level of memory for the windows world. Imo osx base was fine with this for obvious reasons ; )

I have 8gb of Ram. I could add more. I would have to discard what's there to add more.

gehenna

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#1223612 27-Jan-2015 21:45

8GB RAM on a 27" iMac with Windows running via Boot Camp will perform admirably. The RAM won't matter so much as the disk.... is it SSD or not? Probably not... either way it'll perform very well just disk access/write speeds will be slower without an SSD.

MikeB4

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#1223614 27-Jan-2015 21:48

gehenna: 8GB RAM on a 27" iMac with Windows running via Boot Camp will perform admirably. The RAM won't matter so much as the disk.... is it SSD or not? Probably not... either way it'll perform very well just disk access/write speeds will be slower without an SSD.

It has a 1TB drive.

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