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glitch44

macrumors 65816
Original poster
Feb 28, 2006
1,126
161
I'm curious-- can you boot DOS on an intel mac? Not dosbox, not a emulation of some sort, but actually boot DOS from a flash drive/ cd rom?
 
Boot Camp provides a module for the EFI to "emulate" a regular BIOS, which allows non-EFI compliant OSes (aka Windows, Linux, etc.) to boot on these machines.

I don't know how complete this BIOS layer is, but if it was complete, DOS could boot. However... I bet this BIOS code is very limited.

Anyway... why would you want to do that when you have Parallels? ;-)
 
Curious... why would you want to boot/install DOS anyway?

Parallels runs SOOOO slow. I have a new imac and running windows is like watching pickles slide down a glass window. I will give DOS a try, but there is a lot of overhead, (OS X, The Emulator, The reduced speed of emulation, the other operating system, the emulated program you are running)

In a booted form, all you have is the OS and the CHIPSET emulation. Not soft emulation. Plus the program you are running. There seems to be much less room for errors as well. (I have some experience in this, but the real mark would be someone who had a lot of experience in this)

Brendan
 
Yes. I've done it from a CD to flash the firmware on video cards.

How did you do it? I have a 250GB Samsung drive that needs a firmware update and comes with a bootable ISO (boots freeDOS).

It will boot on my windows machine, but the windows box doesn't have Sata internally.

I wasn't able to get it to boot on the mini.
 
1gig of ram with a separate ram for the vid card is not enough? There is no other program that really slows down my computer.
Do you have 1GB RAM on your machine or have you allocated 1GB of RAM to your parallels virtual machine. If you have 1GB total in you mac then you will probably need more RAM.
 
How did you do it? I have a 250GB Samsung drive that needs a firmware update and comes with a bootable ISO (boots freeDOS).

It will boot on my windows machine, but the windows box doesn't have Sata internally.

I wasn't able to get it to boot on the mini.

All I do to boot from a bootable DOS CD is: insert the CD and restart holding the C key. Never had to do anything else special...
 
Parallels runs SOOOO slow. I have a new imac and running windows is like watching pickles slide down a glass window.

Have you tried VMWare Fusion? I use Windows XP in Fusion, although admittedly only for IE compatibility but it works fine with the iMac 1GB 2.0
 
Parallels runs SOOOO slow.

How fast Windows runs under Parallels or VMware depends on how much memory you allocated to the virtual machine. You say you have 1gig. Is that a 1gig Mac? or a Multi-gig Mac with 1 gig allocated to the VM?

I have a MacPro with 1gig allocated to Parallels, and a MBP with 932MB allocated to Parallels, and both of them scream under Windows.

So I believe you problem is configuration. and more RAM is probably your answer.
 
1gig of ram with a separate ram for the vid card is not enough? There is no other program that really slows down my computer.

You have some problem other than Parallels. As the other said, is that 1 GB RAM total, or 1 GB allocated to your Parallels VM? Actually...either way, it should be enough. I don't want to blame it on Parallels, since I know most people don't have trouble with it, but there's something else going on here if it's running that slow for you. I have a 2 GB MacBook with VMWare Fusion. I gave my Windows XP virtual machine only 512MB RAM, and it still flies. Faster than my last PC laptop, even.
 
You have some problem other than Parallels. As the other said, is that 1 GB RAM total, or 1 GB allocated to your Parallels VM? Actually...either way, it should be enough. I don't want to blame it on Parallels, since I know most people don't have trouble with it, but there's something else going on here if it's running that slow for you. I have a 2 GB MacBook with VMWare Fusion. I gave my Windows XP virtual machine only 512MB RAM, and it still flies. Faster than my last PC laptop, even.


I disagree with 1 gig of ram being enough to run parallels well.

I have a friend who upgraded his MBP to 2 gigs of RAM recently. He noticed a significant boost to parallels performance.

If you take a look at this thread: https://forums.macrumors.com/threads/342278/ , you'll see that most people recommend at least 1 gig for the typical user.

But that's BEFORE you split that in half with parallels (not that you have to use half, but you know what I mean).

If your mac flies with 1 gig of ram with typical use, then it will probably fly noticeably faster with more of it.

If you really want an accurate assessment though, there are two things you should look at.
Note: you can do both of these in Activity Monitor, but I recommend you download the iStat Pro widget as it makes it very easy to periodically check your systems stats.

1) Take a look at how much available RAM you have. Not just how much FREE ram you have though. You want to look at inactive+free. Inactive RAM is not really being used by anything right now, but still contains the information it was being used for.
For example, if you open up an application and close it, whatever RAM that application used will be labeled now as inactive. If you then reopen that application, it should open more quickly because instead of having to load the info back into RAM from scratch, it can just use what was left in the inactive RAM. If the system is running low on RAM, then it can easily clear the inactive RAM and use it for whatever task it deems necessary.

2) Take a look at your page ins/outs. I don't know what number you want there though, but generally a lower number is better. The amount of paging though will also depend on how long the machine has been running since the last restart.

If your available ram is very low of if you have lots of paging, then you'll probably benefit from more RAM.
If you're playing any games that are require more performance than a typical game of tetris, then you should probably get more RAM regardless.
 
SpinRite!

Boot Camp provides a module for the EFI to "emulate" a regular BIOS, which allows non-EFI compliant OSes (aka Windows, Linux, etc.) to boot on these machines.

I don't know how complete this BIOS layer is, but if it was complete, DOS could boot. However... I bet this BIOS code is very limited.

Anyway... why would you want to do that when you have Parallels? ;-)

I wonder if any of this can be used to make SpinRite usable on a Mac laptop (e.g. MacBook MacBook Pro). It already boots and launches - see
561798480
.

Removing a laptop HD is usually very time consuming. If the right device drivers could be found and put on the SpinRite CD, it would work?

I just had another idea. SpinRite could be modified to run unprompted.

FYI, I have vmware.

(Please, no pro or anti-GRC zealotry!)
 
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