Can a Dell Windows XP disk be used on an HP?

[MidiMagic]

I have a Dell Optiplex PC with a legal copy of Windows XP. But the Dell hardware seems to be failing. The problem is that the XP distribution CD I got with the computer is a Dell distribution disk, possibly with files specific to Dell (It says both Dell and Microsoft).

If I can't fix the hardware, I need to find a way to transfer my hard drive or the OS and software to another computer. How much different is a Dell Optiplex from a newer HP computer I have (with Linux installed)?

I used a standard Microsoft XP installation CD to install a similar HP computer for my wife (and I know I can't use that CD again because of copyright greed). But I don't have another CD except the Dell. I also want to preserve the installations of two pieces of software that can't be installed again because the companies (and their licensing websites) have gone out of business. So here are my real questions?

I need XP because I have legacy software I made hundreds of files in. I must not lose these files.

1. What would happen if I took the still working hard disk out of the Dell and put it in the HP in place of (or in addition to) the disk that is in it? Are there any serious incompatibilities (like there was between the DOS for Compaq computers and the other versions of DOS)?

2. Is there a way to place a disk image of the Dell hard disk onto the hard disk in the HP, including the boot sector and registry? That drive is much larger.

3. Can I install the Dell disk in the HP (assuming I remove Windows from the Dell once I am successful)? Or will incompatibilities prevent it?

4. Is there any way to transfer the installations of those two pieces of software? I paid good money for them, and I should be allowed to keep using them even though the computer died.

5. If I put both hard disks in one computer, how easy is dual boot? And are the file formats different?

[ggeoff]

Just replying to item 3. The Dell disk can be used in any make of PC. That's what sellers say on eBay.

You could buy a used Optiplex with XP for not much more than buying XP on its own or a Dell workstation a 490 for about 120GBP.

[rubberman]

You probably can't boot from it on the HP since the CPU and BIOS IDs will have changed, and the HP uses different drivers than the Dell so XP won't like it, but as a second disc, you can access/use it for data storage and installing new software.

[MidiMagic]

But I need it for XP too.

[rubberman]

Each OEM version of Windows XP (or otherwise) has its own drivers, and other cruft that verifies that it is running on the correct hardware. IE, trying to boot a disc from a Dell system on an HP (or vice versa), generally won't work. I have tried running such on XP virtual machines in the past with no luck. You can purchase a version of XP (or could in the past - may have to get Win7 now, which I did) which is not tethered to any specific hardware. I purchase Win7 to run in a virtual machine so I could run some Windows software that I could not in my Linux systems under Wine. Works fine. I think I spent around $100-$130 for the disc. At least Win7 can run XP software pretty well for the most part.

[MidiMagic]

Having the same system, bus, and I/O timing is crucial for these real-time applications. I already tried running them on Windows 7 (started from an install disk), and they produce wrong results.

It is the usual case that, when you upgrade to a new version of the operating system, you have to get new software for almost all real-time applications. The problem is that I can't get an upgrade, because (as has happened all too frequently with real-time applications) the company didn't have the Vista version ready when Vista was supplanted by Windows 7. They went out of business because they can't keep up with the Microsoft upgrade schecdule.

Most real-time software that has been written was released for MS-DOS, Windows 3, and Windows XP. There was time to develop and test the software before Microsoft changed the OS again. And most of the companies that made this kind of software were driven out of business when Microsoft again started releasing new systems in rapid succession.

[Hiroshe]

Technically it is illigal (breach of eula, each copy is windows is licensed to be installed on one computer).

You might be able to get it to install, but I dout you would be able to activate it (they lock it in by checking it against your hardware).

I've heard that windows 8 had some rtc problems, but there fixed now. I haven't heard too much on the topic of real-time applications and differences between operating systems. Is this because your particular software is using non real-time system calls and basing it's "real-timeness" off of the expected behavious or said system calls? I guess that works for non-critical stuff, but you'll be in trouble when the behaviour changes with an upgrade.

The authors of the software should have either used an RTOS (thus assuring that it does run in real-time and isn't starved) or avoided using non real-time system calls in the first place (even if they need to write there own drivers to avoid it).

[MidiMagic]

So what do you do when that computer dies and must be replaced? I still have the licence, and I will be using it on only one computer, but not THAT computer.

They have to write their own drivers because the Windows I/O system is not fast enough. Windows does I/O only once every 55 ms. I need 1 ms resolution. I had 1 ms resolution with MS-DOS, and with XP. But Microsoft will not leave the system timing alone, so the drivers they wrote for XP don't work with Vista, 7, or 8.

I am not going to Windows 8 for another reason: I totally hate cell phone type interfaces.

I am sick of people telling me what I can't do. And I am especially sick of copy-protection software telling me I can't do something to keep what I have.

[Hiroshe]

So what do you do when that computer dies and must be replaced? I still have the licence, and I will be using it on only one computer, but not THAT computer.

Each copy of Windows may only be installed on one computer. After it's installed on one computer, it may only ever be installed on that computer. The license is non-transferrable. They've got it knotted up pretty well.

They have to write their own drivers because the Windows I/O system is not fast enough. Windows does I/O only once every 55 ms. I need 1 ms resolution. I had 1 ms resolution with MS-DOS, and with XP. But Microsoft will not leave the system timing alone, so the drivers they wrote for XP don't work with Vista, 7, or 8.

You've mentioned that you got your program to run on the system, but it's giving you the wrong results. I assume that means you got your drivers to install properly. Since your program is no longer running in real-time, that means that the drivers or the program is relying on some system call which was never guerenteed to be real-time in the first place. (Since windows doesn't guerentee real-timeness, it allows them to make power optimizations, as well as seek time optimizations, etc... while assuming that real-time programmers will use Window CE, some other RTOS, or carefully making their own drivers).

I am not going to Windows 8 for another reason: I totally hate cell phone type interfaces

Me too. I prefer the command line, tiling window manager, or a more desktop like environment (for the sake of familiarity, if nothing else) in that order. Cygwin took care of the first thing, and Classic shell took care of the last. The second is still not easy in windows unfortunatly, but it doesn't effect workflow too much.

I am sick of people telling me what I can't do. And I am especially sick of copy-protection software telling me I can't do something to keep what I have.

Use open source software then. Proprietary software does restrict what you can and cannot do, and you'll need to listen to the vendor (which is why you should choose responsible companies). Open source software also imposes restrictions, but it is designed to give you fair control over it. Also the quality of open source software is fairly competitive, and it will make a lot of projects easier (since you already have the right to modify the wealth of software availible).

[cunnijo]

MidiMagic. Firstly is there a product key attached to the Dell PC and the disc originally came with it then the OS could potentially be installed on another PC, activated and registred with Microsoft. Just insert the CD and boot from startup and enter the product key when prompted. Only the OS is normally installed not the drivers. Some may say it is questionable but can it be explained why Microsoft's own automated systems allow activation if the OS is unique to a certain brand of PC.