Mortandos

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Q: Why can I only use 2.48 GB RAM in Boot Camp (Win 8.1 Pro, 64-bit)?

Hello, I am fairly new to the iMac and I have to use some programs in Windows that are not available for Mac so I set up Boot Camp and installed Windows 8.1.

My iMac is a I7-2600 CPU @ 3.4GHz with 16 GB RAM, system type-bit. Under system in Windows it shows Installed memory (RAM) 16 GB (2.48 GB usable).

I read about this problem and most answers are related to people using 32-bit. So what is wrong in my case, where is the problem?

Thank you in advance for help and suggestions.

iMac, OS X Yosemite (10.10.3)

Posted on May 3, 2015 11:52 AM

I have this question too

Q: Why can I only use 2.48 GB RAM in Boot Camp (Win 8.1 Pro, 64-bit)?

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Loner T

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Jun 19, 2015 10:45 AM in response to Mortandos

The appropriate link should be https://technet.microsoft.com/en-us/library/jj200124.aspx . From this link, step 9 (it is 1 because of renumbering), you should use NTFS, not FAT32, because your Mac is not UEFI-compliant.

To format the partition, type format fs=ntfs quick, and then click ENTER.

Important
If your server platform supports Unified Extensible Firmware Interface (UEFI), you should format the USB flash drive as FAT32 rather than as NTFS. To format the partition as FAT32, type `format fs=fat32 quick`, and then click ENTER.

by Mortandos,

Mortandos Jun 19, 2015 1:15 PM in response to Loner T
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Jun 19, 2015 1:15 PM in response to Loner T

Ok, followed the same procedure except this time formatting the stick as NTFS, no luck, same old "No bootable device" error message. That doesn't make any sense.
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by Loner T,

Loner T Jun 19, 2015 1:26 PM in response to Mortandos
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Jun 19, 2015 1:26 PM in response to Mortandos

Reset SMC and NVRAM and test.
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by Mortandos,

Mortandos Jun 19, 2015 2:14 PM in response to Loner T
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Jun 19, 2015 2:14 PM in response to Loner T

I did - so many times and just did it again, nothing. It doesn't even offer the EFI boot from the USB stick anymore.
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by Loner T,

Loner T Jun 19, 2015 2:30 PM in response to Mortandos
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Jun 19, 2015 2:30 PM in response to Mortandos

Can you try a different USB stick?
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by Mortandos,

Mortandos Jun 19, 2015 3:31 PM in response to Loner T
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Jun 19, 2015 3:31 PM in response to Loner T

I had the same idea, I tried 3 different USB sticks. The most promising suggestion to me is still the small boot partition on the internal hard drive - when you suggested that you said I should format it fat32 or exfat - today when we were talking about the USB sticks you said NTFS - so was it wrong to format the small boot partition with fat? (Though I'm almost sure I tried NTFS just out of curiosity)
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by Loner T,

Loner T Jun 19, 2015 3:51 PM in response to Mortandos
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Jun 19, 2015 3:51 PM in response to Mortandos

How did you make the partition NTFS on the disk0s1? Tuxera?
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by Mortandos,

Mortandos Jun 19, 2015 10:02 PM in response to Loner T
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Jun 19, 2015 10:02 PM in response to Loner T

no, I was actually doing it using Parallels... I can do it again using my Windows laptop but it shouldn't make any difference, right?!
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by Loner T,

Loner T Jun 20, 2015 6:17 AM in response to Mortandos
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Jun 20, 2015 6:17 AM in response to Mortandos

Try the Windows PC, I have reservations about Parallels hacked version of NTFS-3g.
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by Mortandos,

Mortandos Jun 22, 2015 10:23 AM in response to Loner T
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Jun 22, 2015 10:23 AM in response to Loner T

Doesn't work, none of my 3 USB sticks shows up. That is more than strange, don't you think?!

Btw - I came across Winclone and read: Migrate external Windows system to Boot Camp

Does that mean I could migrate the Windows from my Windows laptop to Boot Camp?
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by Loner T,

Loner T Jun 22, 2015 10:31 AM in response to Mortandos
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Jun 22, 2015 10:31 AM in response to Mortandos

Mortandos wrote:

Btw - I came across Winclone and read: Migrate external Windows system to Boot Camp

Does that mean I could migrate the Windows from my Windows laptop to Boot Camp?

Yes.
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by Mortandos,

Mortandos Jun 22, 2015 12:52 PM in response to Loner T
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Jun 22, 2015 12:52 PM in response to Loner T

Have you ever tried that before? Any downsides? Things to consider?
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by Loner T,

Loner T Jun 22, 2015 1:16 PM in response to Mortandos
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Jun 22, 2015 1:16 PM in response to Mortandos

Yes. Remember, this also requires running SysPrep which has a limited number of attempts due to Windows licensing restrictions.
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by Mortandos,

Mortandos Jun 22, 2015 3:42 PM in response to Loner T
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Jun 22, 2015 3:42 PM in response to Loner T

It seems that this is my last option. Any links / documentation that you know of (that are reliable)? Did it work for you?
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by Loner T,

Loner T Jun 22, 2015 5:41 PM in response to Mortandos
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Jun 22, 2015 5:41 PM in response to Mortandos

The Winclone is well written and self-contained. If you buy the product, you will also get Technical Support. I have not run into any issues so far.
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