[SOLVED] MBR and GPT, Dual Boot, 2 HDDs, different windows

Gebaben

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Dec 22, 2016
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Hi there!

Currently I have windows 7 32-bit, and would like to have a windows 10 64 bit OS too on my PC. I definitely want to keep the win7 32 bit OS even if it is old, that is why I don't want a simple OS upgrade. I thought about dual booting on a single HDD, but with the split I've calculated that I would probably run out of space. So I started thinking about getting an another HDD and install win10 on it. The main problem is I am not sure about these MBR and GPT formats. Currently the HDD is MBR with UEFI BIOS and it is running fine. I don't know the new HDD should be MBR or GPT. I know the advantages of the GPT format but not sure if it would boot up with both OS.

Here some pictures of my BIOS settings:
https://ibb.co/zFvYf91
https://ibb.co/G2xb4kx

I've read a post by @Colif on the forum that says: BIOS needs to be set up as Legacy only otherwise the WIn 10 installer will see PC is capable of running GPT drives, and if drive is blank, will format it as GPT whether you want it to or not.

Which settings exactly from the pictures above?
What other settings should I change in BIOS to get both OS working.
And which format should I choose for the new HDD to get the dual boot working fine? MBR or GBT?

About the next picture: I don't know if these yellow SATA6G and brown SATA3G makes difference when installing the new HDD.
https://ibb.co/5xRLLyh

My PC:
MB: ASUS H81m PLUS
HDD: Western Digital 500GB SATA 3.5 (wdc wd5000aakx-08u6a)
8 GB RAM
Intel i5 4460
Nvidia GT 730 2GB GDDR5
 
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The hibernation file can screw up the OS when it's not the OS that it was created for. For example yo hibernated win7 last night but now you need win10 so you boot that. BAM you get checking drive for error messages on your drives and letting the wrong OS fix them leads to corruption. I disable indexing as well because I was sick and tired of something doing it and was trying to stop win10 from accessing drives unless I needed it to, plus it doesn't work great anyways. I think large drives are too big for it.
Again only Win8 &10 have this behavior mostly because Shutdown doesn't really shutdown; it's a hybrid sleep and guess what that does...

Does this work on all motherbds? - beats me but I've been doing this since about 97...
How large capacity will the new drive have?

GPT partitioning is necessary for drives larger than 2TB.
If your new drive is less than 2TB, then partition it in MBR and install windows 10 in legacy mode.

If your new drive is larger than 2TB, then you'll have to partition it in GPT. Or else full capacity is not available.

Then you have to decide on bootloader.
You can use same bootloader for both windows 7 and windows 10. This is more convenient. Problem here - both drives need to be present to boot windows 10.

Or you can use separate bootloaders. Then both OS will be independent. But then you have to use BIOS to switch between booting into one OS or another.
 
How large capacity will the new drive have?

I will plan to get a new HDD with around the same size as the current one. So 500GB.

both drives need to be present to boot windows 10.

Well I don't plan to plug one of them out and use them in turns if that is what you mean. I would like to use them at the same time, moving files between them.

Should I change the Boot Device Control setting in BIOS under the CSM options? (see first image in my first post)
 
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Not true.
MBR can use/access/boot from drives larger than 2TB. You would just have to use multiple partitions on those drives that do not exceed ~2TBs each.
That is only true if the sector size is increased. Otherwise, for a 512e drive, the maximum size for MBR partitioning is still only 2TiB. You cannot have four 2TB partitions. The reason is that the maximum number of LBAs is limited to a 32-bit value, as is the starting sector for each partition.
 
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Not true.
MBR can use/access/boot from drives larger than 2TB. You would just have to use multiple partitions on those drives that do not exceed ~2TBs each.
Have you tried it? Probably not.

This is, how 3TB MBR partitioned drive looks like.
See unallocated space past 2TB mark. New partition in that space can not be created.

new-simple-volume-grayed-out.png
 
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You won't need to enter the bios to change which drive you boot with if you use independent boot loaders.
First you'll need to disable fastboot in the bios due to win7/win10 issues that it will cause.

Then you just need to install that OS with only that drive in the system to get separate bootloaders.
- if you have the means to, make backups of the drive once you get the OS installed. I typically install the drivers as well before moving onto the next OS.
- When you first install win10, disable hybernation right from the start. This should also disable fast startup as well. which is what you want to do also.

When done with the second OS, Power down, connect the other drive in so both are installed, Boot into the Bios & Set your main OS as the 1st boot drive and the other one as the 2nd.
- When you want to boot your main OS you don't have to do anything.
- When you want to boot the other one, you just hit the F-key to select the boot device. Which F-key that is depends on your motherbd bios but it will tell you on screen at the same time it tells you to press Del to enter setup. On my MSI it's F11. It was F10 on my previous Gigabyte. I have 3 OS's installed and use this feature often.

I also boot into each OS and disable indexing on the other drive. I don't want 10 messing up the 7 drive or vice-versa. I been thru enough re-installs already (thanks heavens for backups!)
I thought there was something else but I'll have to wait until I get home to check on a system with more then 1 drive in it.
 
So...
1: Plug in second HDD
2: Boot up and format the new HDD to MBS
3: Then restart and disable fastboot, set Boot Device Control to Legacy only
4: Then turn off PC and plug out first HDD
5: Install win10 on new HDD
6: Install drivers on win10 and disable hybernation
7: Plug back first HDD and set main OS in BIOS
8: Disable indexing on both OS

How can I disable the indexing? This means I won't be able to move files between the 2 HDDs?

Also disabling hybernation means it won't be a good idea to put the PC into sleep mode?
 
It is not too hard to run two different OS'es.
I did so on a laptop where I wanted a 32 bit os to continue to rum Civilization II which is a 6 bit program and will only run on a 32 bit os.
It is probably simplest to simply use the bios boot option to pick the device you want to boot from.

If you need more than 4gb of ram, or support for newer hardware, that is only going to come from a 64 bit os using windows 10.

I looked into a virtual machine, but that seemed too awkward.
Eventually, I installed windows 10 32 bit on a second desktop to run civ II.
There are still nvidia drivers for 32 bit windows 10.

If you will install windows 10 on a drive, do not have any other drive connected.
If you do, windows will put a hidden recovery partition on it, making it all but impossible to ever run without the second drive.

While windows 10 32 bit is working, it seems that windows keeps pushing out a new version update.
It goes through the process and at the end finds that it had a problem and restores the current working version.
This has happened twice.

I am thinking about dumping windows and reverting to windows 7 just for running CIV II.

Regardless, do plan on using a ssd for all of this, you will not regret the decision.
 
1: Plug in second HDD
2: Boot up and format the new HDD to MBS
3: Then restart and disable fastboot, set Boot Device Control to Legacy only
4: Then turn off PC and plug out first HDD
5: Install win10 on new HDD
6: Install drivers on win10 and disable hybernation
7: Plug back first HDD and set main OS in BIOS
8: Disable indexing on both OS

How can I disable the indexing?
This means I won't be able to move files between the 2 HDDs?
Also disabling hybernation means it won't be a good idea to put the PC into sleep mode?
Unnecessary complicated. Too many steps.
  1. Disable hibernation in windows 7.
  2. Shutdown pc. Disconnect all old storage drives. Connect new HDD only.
  3. Disable fast boot, set boot control to legacy in BIOS.
  4. Install windows 10 in legacy mode (clean HDD before install). Afterwards - install drivers, disable hibernation.
  5. Reconnect old storage drives.
  6. Verify you can boot into either OS by changing boot priority settings in BIOS.
How can I disable the indexing?
Forget about indexing step. Not necessary.
This means I won't be able to move files between the 2 HDDs?
No. It doesn't mean that.
Also disabling hybernation means it won't be a good idea to put the PC into sleep mode?
That means - hibernation will not work, hybrid sleep will not work.
Normal sleep will still work. Sometimes drivers can prevent system from going into sleep/waking up though.
 
You won't need to enter the bios to change which drive you boot with if you use independent boot loaders.
First you'll need to disable fastboot in the bios due to win7/win10 issues that it will cause.

Then you just need to install that OS with only that drive in the system to get separate bootloaders.
  • if you have the means to, make backups of the drive once you get the OS installed. I typically install the drivers as well before moving onto the next OS.
  • When you first install win10, disable hybernation right from the start. This should also disable fast startup as well. which is what you want to do also.
When done with the second OS, Power down, connect the other drive in so both are installed, Boot into the Bios & Set your main OS as the 1st boot drive and the other one as the 2nd.
  • When you want to boot your main OS you don't have to do anything.
  • When you want to boot the other one, you just hit the F-key to select the boot device. Which F-key that is depends on your motherbd bios but it will tell you on screen at the same time it tells you to press Del to enter setup. On my MSI it's F11. It was F10 on my previous Gigabyte. I have 3 OS's installed and use this feature often.
I also boot into each OS and disable indexing on the other drive. I don't want 10 messing up the 7 drive or vice-versa. I been thru enough re-installs already (thanks heavens for backups!)
I thought there was something else but I'll have to wait until I get home to check on a system with more then 1 drive in it.

Are you certain this method works with every motherboard?
I think it's better to do it using the Windows bootloader method.
 
Hibernation works by recording the contents of ram to the hiberfile.
On wake, the contents of ram are restored exactly from that file.
If you do not need to ever preserve ram contents while sleeping, then turn hibernate off.
Use sleep to ram instead.
Even then, ram contents are preserved.
The only caveat is if ram contents are essential.
Then with sleep to ram, such contents will be lost if there is a power outage.
Sleep to ram saves time from not having to dump ram contents, only to restore empty contents.
sleep/wake are faster.

The bootloader method requires that you have both drives present.
By selecting a boot device from the bios or(usually spamming F12) you can boot with only that single device present.
In the normal case where both drives are present, you will be able to access data folders from either drive.
 
Well I use sleep mode only. So hybernation is useless for me and I will turn off it then.
BTW in the meantime I've decided I will rather get an SSD instead of a second HDD.

The bootloader method requires that you have both drives present.
By selecting a boot device from the bios or(usually spamming F12) you can boot with only that single device present.
In the normal case where both drives are present, you will be able to access data folders from either drive.

I would like to use them together.( both connected all the time)
If I have understood correctly, it will possible to move/copy data from one drive to another, even if I install win10 while win7 is removed.
 
Well I use sleep mode only. So hybernation is useless for me and I will turn off it then.
BTW in the meantime I've decided I will rather get an SSD instead of a second HDD.



I would like to use them together.( both connected all the time)
If I have understood correctly, it will possible to move/copy data from one drive to another, even if I install win10 while win7 is removed.

I think you are good.
It is best to install windows 10 on a single drive without any other drive connected,
If there is a second drive connected, windows will place a hidden recovery partition on it, making it all but impossible to boot without that second drive present.
With only a single drive present, that partition will be placed on the same windows 10 drive.

After install, you can reconnect any other drives, and the data folders on them will be fully available.
 
If there is a second drive connected, windows will place a hidden recovery partition on it, making it all but impossible to boot without that second drive present.
With only a single drive present, that partition will be placed on the same windows 10 drive.
It is not recovery partition, you have to worry about. It is bootloader partition. Not the same thing.
If a bootloader already axists on another drive, then new one doesn't get created during windows isntall.
System without bootloader can't boot into OS. You remove drive with bootloader, system becomes unbootable.
 
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The hibernation file can screw up the OS when it's not the OS that it was created for. For example yo hibernated win7 last night but now you need win10 so you boot that. BAM you get checking drive for error messages on your drives and letting the wrong OS fix them leads to corruption. I disable indexing as well because I was sick and tired of something doing it and was trying to stop win10 from accessing drives unless I needed it to, plus it doesn't work great anyways. I think large drives are too big for it.
Again only Win8 &10 have this behavior mostly because Shutdown doesn't really shutdown; it's a hybrid sleep and guess what that does...

Does this work on all motherbds? - beats me but I've been doing this since about 97 but it's only since Win Vista, I think, that you had to disconnect all the other drives because it puts the boot loader somewhere else if you don't.
 
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