SM951 shown as external drive, problem with Bootcamp

Beagl3

macrumors newbie
Original poster
Jan 2, 2016
19
4
Germany
Hey guys,

i installed a 256GB Samsung SM951 AHCI in my machine today. But the PCIe drive is recognized as external storage, which makes it impossible for me to install Bootcamp on it. In an older thread on MacRumors, i read about a kernel extension, which makes PCIe drives recognized as internal ones, so i would get usable for Bootcamp. I just downloaded the generic kext and threw it into kext drop in order to install it, but after a reboot, everything remained the same. Does anyone know what i've done wrong?
I'm grateful for every answer,

Beagle
 

ActionableMango

macrumors G3
Sep 21, 2010
9,555
6,819
Hmmm, I'm not understanding the problem.

Windows sees the SM951 as an internal drive. Install Windows to the drive from the USB installer. Install bootcamp drivers afterward via direct download from Apple.

You don't need OS X, and in fact I'd recommend removing the OS X drive during all this so that the Windows installer doesn't get too excited and mess it up.
 

Beagl3

macrumors newbie
Original poster
Jan 2, 2016
19
4
Germany
The original plan was to use the SM951 as boot drive for both operating systems. My actual question was, how to geht the kext working. Is the Windows partition also recognized in the preferences when installed without Bootcamp?
 

Draeconis

macrumors 6502a
May 6, 2008
969
264
The original plan was to use the SM951 as boot drive for both operating systems. My actual question was, how to geht the kext working. Is the Windows partition also recognized in the preferences when installed without Bootcamp?
As I understand it, it isn't that simple. You may have some luck installing Windows to a drive in Bay 1 or in the ODD bay, then transferring that into the SM951, but much like people trying to boot Windows from SATA-III boards, this will have limited if no success.

There are guides on this forum for the latter, but I could never get any of them to work, apart from possibly forcing AHCI mode, but I can't seem to verify that accurately.
 

ActionableMango

macrumors G3
Sep 21, 2010
9,555
6,819
Oh sorry, I misunderstood. When you said "install bootcamp" I thought you meant installing the bootcamp drivers. But I see now you are trying to use Bootcamp Assistant to partition the drive for multi-OS use.

If you are using Yosemite or El Capitan, I suspect it's just that these operating systems have made signed KEXTs mandatory and these are probably unsigned KEXTs.

You can check to see which KEXTs are actually loaded and running in System Information.

In Yosemite you can disable KEXT signing requirement at the command line and then rebooting:
sudo nvram boot-args='kext-dev-mode=1'

I've heard this ability was removed in El Capitan. I wouldn't know what to do about that, but I think disabling SIP will work. Not sure.

However, Draeconis makes a good point that trumps all this. Even if you solve this problem, you're stuck. When installing Windows to a bootcamp-assistant-partitioned drive with hybrid GPT/MBR, Windows wants to install in BIOS mode, which won't run on an AHCI-only device like your blade.
 
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orph

macrumors 68000
Dec 12, 2005
1,884
391
UK
do you want windows and osx on the same drive? or is it going to be a dedicated windows drive?
last few time's i installed windows 7 on a HD in my mac pro all i did was;
grab newest bootcamp drivers on to a usb stick
pull all HD's out of my mac apart from the one windows is going on
install windows 7 on to the drive
instal drivers, download gpu drivers then update os (takes ages)
then turn of and put back in all my HD's

always seems to work fine for me, i think you only need to use the Bootcamp app if you want osx and windws on the same drive.

ps if your copy of osx is to new you can always install an old version on to a usb stick
 

LiamKelly

macrumors newbie
Apr 29, 2016
10
1
Hmmm, I'm not understanding the problem.

Windows sees the SM951 as an internal drive. Install Windows to the drive from the USB installer. Install bootcamp drivers afterward via direct download from Apple.

You don't need OS X, and in fact I'd recommend removing the OS X drive during all this so that the Windows installer doesn't get too excited and mess it up.
Windows (not even the cd or usb installer drive) will not boot when the sm951 is installed in the machine. Remove it and they boot, install it and get a disk read error.
 

Obioban

macrumors regular
Oct 19, 2011
129
1
So if you want to install a bootcamp windows boot on an SSD on something faster than SATA2... what's the best option?
 
Jul 4, 2015
4,488
2,548
Paris
So if you want to install a bootcamp windows boot on an SSD on something faster than SATA2... what's the best option?
What's the point? SSD boot times won't improve if you go beyond SATA 2 (on OSX or Windows). The difference is within margin of error (none)

http://www.tomshardware.com/reviews/ssd-upgrade-sata-3gbps,3469-13.html

http://www.overclock.net/t/1489684/ssd-interface-comparison-pci-express-vs-sata

http://cdn.arstechnica.net/wp-content/uploads/sites/3/2015/10/Bootracer-980x735.jpeg

It's fine to install the boot volume in SATA 2 SSD and use a faster interface for another drive for things like very large media file editing, multi gigabyte games, etc
 

Obioban

macrumors regular
Oct 19, 2011
129
1
What's the point? SSD boot times won't improve if you go beyond SATA 2 (on OSX or Windows). The difference is within margin of error (none)

http://www.tomshardware.com/reviews/ssd-upgrade-sata-3gbps,3469-13.html

http://www.overclock.net/t/1489684/ssd-interface-comparison-pci-express-vs-sata

http://cdn.arstechnica.net/wp-content/uploads/sites/3/2015/10/Bootracer-980x735.jpeg

It's fine to install the boot volume in SATA 2 SSD and use a faster interface for another drive for things like very large media file editing, multi gigabyte games, etc
Because I only want one windows drive, for boot and games and 3D model files.

Soooo, is there a faster than SATA2 interface I can use to boot into windows via bootcamp?
 

h9826790

macrumors G5
Apr 3, 2014
14,400
6,951
Hong Kong
Because I only want one windows drive, for boot and games and 3D model files.

Soooo, is there a faster than SATA2 interface I can use to boot into windows via bootcamp?
SATA 3, but may still need some special procedure (e.g. install via SATA 2, and then transfer the SSD onto the card).

There are some tutorial about how to install Windows on external drive (mainly for USB drive), may be you can follow those tutorial and install Windows onto your PCIe SSD.
 
Jul 4, 2015
4,488
2,548
Paris
Because I only want one windows drive, for boot and games and 3D model files.

Soooo, is there a faster than SATA2 interface I can use to boot into windows via bootcamp?
You won't benefit much to be honest. There are only a few games that unpack very large files in memory. It's people handing very large media projects who need that bandwidth. Maybe in 2-3 years operating systems and games will become 'fat' enough to utilise more bandwidth, but by then you wouldn't want to use an old cMP anyway. The CPU will hold you back.

Here's some more real world performance of the fastest PCIE SSDs vs SATA 3 vs SATA 2

http://www.tomshardware.com/reviews/sata-6gbps-performance-sata-3gbps,3110-7.html

http://techreport.com/review/29221/samsung-950-pro-512gb-ssd-reviewed/

Then you have capacity and cost per gigabyte issues to consider. A gamer should be happier with a 2TB+ SSD in their SSD 2 bays than having a 512GB PCIE SSD. My Steam library can't fit on half a terabyte and I'm a very casual and rare gamer.
 
Last edited:

Obioban

macrumors regular
Oct 19, 2011
129
1
Is there a faster than SATA2 interface I can use to boot into windows via bootcamp?
 
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