Vista on my MacBook

Post Reply New Topic

@Computerlove: I don't think I want to run it in virtualization. For one thing, I plan on having a triple-boot system and primarily using Ubuntu still. I would rather have separate access to each OS. Plus, I don't think the tech place will be willing to install it via Parallels or VirtualBox.

What do you mean the most that can be used is 3GB? 4GB is where my computer maxes out on RAM.

Well, that's great, but I don't have XP and can't access it without actually buying a copy. Vista for $0 (legally of course) is probably better than XP at whatever it costs to buy.

What? There is no limit on the number of logical partitions. They form a linked list. You may have come across some application that limits them... I haven't (yet).

Ah!... but... if you have to use Windows, I suppose you are stuck with a maximum of 26 mounted "drives" (as Windows doesn't understand partitions, etc), Then "A:" and "B:" are floppy drives... leaving 24 for partitions, so if you have a drive (real drive) with an extended partition containing 16 logical partitions, plus you happen to use all three of the other MBR slots for primary partitions (you don't have to do this), then.... that still leaves five letters?

Yeah. Windows is a bit limited with its "drives".

(I only have 20 active mounts on this machine, since I moved one of my drives with its dozen partitions onto the other machine.)

===============

I haven't installed Vista. I doubt that I would risk installing it on a drive where I had anything else. In fact, I'd remove any additional drives, just to be safe.

I have installed a second copy of XP on a drive with an existing XP in another partition, and multibooted those with several Linux installs, all on the one drive. My original XP had become so damaged, it was getting to be unusable. In order to fool the install so it could not see that it was already installed on the first primary partition, I changed that partition's type, temporarily. The new XP went into a logical partition. I then re-enabled the original XP, so I could still get to it, if need be.

Installing XP wrecked the MBR - i.e. it broke the Linux boot. I could have just patched that back in, but I decided to let XP have its evil way, and went over to using "bootpart": http://ourworld.compuserve.com/homepage ... otpart.htm

Then, for a long while, I managed the old XP via grub, and booted it up once every few months. Now, as I never reboot, I've stopped using the "real" XP at all, and have re-installed an XP as a VirtualBox client.

=========

Anyway, back to logical partitions.... it was probably was what caught you, earlier on, when you didn't seem to be able to use half your disc.

There is a typical "install Ubuntu while reducing the size of what looks like the single gigantic partition on a drive". What happens is that the manufacturer has formatted the drive with a small concealed primary partition that held some "recovery" stuff, and a huge single, visible primary partition.

The default for Ubuntu seems to be to let you contract the large existing primary and allocate most of the freed area as a primary partition for its root filesystem.

Now Linux likes to have a "swap" partition. Ubuntu allocates a small area for this. However, it is "smart", and puts this inside an extended partition (because it may be going to create other partitions, but in the default case, it doesn't).

So you end up with a small primary, recovery partition, a big, original system primary, another big Ubuntu primary, the fourth primary slot being the minuscule extended partition, with a single tiny logical partition inside it.

If you decided to re-use the space from the Ubuntu area, you may try to reduce the size of that partition, leaving a big gap after it. However, you'll now find that you can't create a partition in that space. The problem is that all the four primary slots as in use, still. The fact that one is the extended partition doesn't help, because it is tiny, and doesn't cover the spare space:

[<-P1->][<----P2---->][<-P3->][<-----Spare space----->][E[L]]

If that is roughly how your drive looks, the trick is just to extend the extended partition to encompass as much of the drive as you can. It makes for the most flexible way of managing the space. At minimum, change something like the above to look like:

[<-P1->][<----P2---->][<-P3->][<------------E------------->[L]]

The partition issue is fixed now.

And the problems with XP and Vista mentioned are the ones the tech place has with whatever method they use- involving BootCamp, I believe, but I'm wondering why it will take them a week to do it. Ah well. In about a week we'll find out how this works.

Fingers crossed.

Thanks lau. I heard there was a limit to primary partitions and assumed that applied to the contents of extended ones as well. I appreciate the correction.

Just to complete the picture... that should read "the extended one". On a drive you can have up to four primary partitions, or ONE extended partition and up to three primary partitions. A cruddy early design decision, with no provision for more than four partitions, followed by an equally cruddy recovery from that to allow an even bigger tangle of partitions. At least it was upwardly compatible.

Why on Earth would you want to install Vista on your MacBook? Considering it's a MacBook and not a MacBook Pro you can't play any games which is the main reason you would require a native install. Try virtualization software if you're looking to run Windows applications, far easier and you don't have to leave the comfortable mac environment.

Long story short, its the way they address memory in the operating system. Some of the address space is wasted/used for other things. I've got four gigs in my xp machine, which shows up in the bios/boot tests, but in xp itself: 3 gigs. Its like new houses at the end of the street that havent been given numbers yet.

*waits for lau's excellent technical explanation.*

Briefly, fuzzy, the disappearance of one of your four gigabytes is because your particular version of XP has stolen it for its own nefarious purposes (whatever they might be).

This seems to be a fairly comprehensible explanation of Microsoft's approach:
Memory Support and Windows Operating Systems

This goes into detail that fried my brain:
Memory Limits for Windows Releases

Anyway, the "4 gig, but you can only see 3 of them", seems to be purely a constraint imposed by M$ in their software, and nothing to do with the hardware.

Generally, the physical memory limit is just based on how many wires make up the address lines, although the 16 Mbyte Intel system I worked on got round this by tricks like "activating" which memory card (yes, one rack mounted card for each megabyte) should be "in use".

However, I've also worked on machines that do things like reserving a hex digit as a "hardware device" selection. I.e. when the top four bits of an address put on the address bus are all set, no attempt is made to access memory at that address. Some further address lines are used to select a particular hardware device, and the remainder of the address lines are interpreted by that hardware device in whatever fashion it wishes. (That was on a Motorola 68008 based bit of kit, which was NOT using the standard Motorola I/O hardware scheme.)

The Unibus is also typical of this sort of game, where there was an 18 bit address bus (on a 16 bit machine), and (typically) the 5 top bits set reserved an 8K addressable space for I/O control. (And yes - I've worked on PDP11s)

Yes, I am aware what happens and approximately 1GB is used by the software. The 4GB is recognised by the BIOS, but amazing you can use 3.5GB using an alternative OS, such as Linux. I am more aware about what goes on, you just never gave me time to catch up on it. I like to give information as necessary. I've learnt not everyone can take the amount of information on software, OS and hardware that I can.
I'm personally not one to read a long post just to get a simple yes or no.

You may want to look at:
Explore the Linux memory model
Linux also (dependent on kernel and processor concerned) may impose a 3Gbyte limit on application's user space. It's not that "approximately 1GB is used by the software", it's that there are difficulties involved in the Intel architecture. As the article says, it is a choice to use a 3:1 ratio.
I'd be interested to know where your 3.5Gbyte figure comes from. I guess there are ways of getting a 7:1 ratio to be tolerably efficient.

And then, staying with 32-bit, there's still PAE, to enable use of 64 Gbytes of physical memory under Linux, Solaris and some (heavy) versions of Windows (not desktop XP or Vista, both of which stick at 4Gbytes).

Some figures, I got from the top of my head - therefor not 100% guaranteed to be correct

I'm lost with the technical details here, so let me see if I understand the end result. With 64-bit architecture, it's impossible to use more than 3GB RAM? Why then are computer manufacturers selling machines with such specs (and higher)? What will happen when Wirth's Law gives us even more bloated software to the point that more than 3GB RAM is needed?

Relax Vista will run finr, Just don't expect all printers or flash drives to work unless the box states they are compatible with vista.

No. I was speaking entirely about 32-bit Intel architectures. With the PAE, they are quite capable of accessing 64GiB (I.e. 36-bit physical address bus).

Once you step into 64-bit, the game changes:
Current 64-bit microprocessor architectures

However, to quote from http://en.wikipedia.org/wiki/Vista_64


I find that interesting - M$ was already supporting 64GiB of physical memory on 32-bit processors, and are now allowing for double that on 64-bit processors.

=============

I remember when more than 32KiB was a dream.

So in that case, my computer could use 4GB of RAM just fine if I installed that amount on it?