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Must I reformat if I replace my motherboard?

Question: I want to replace the motherboard in my computer which is running Windows Home. I have been told that I must format the existing hard drive and reinstall the operating system before the computer will recognize the new motherboard. Is this true?

It’s not always true, it’s usually at least half true, and in reality it’s practically true.

Truth can be confusing, can’t it? Let me explain …

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Replacing the motherboard is pretty darned close to building a new machine from scratch. It really is the heart and soul of a machine, as well as it’s brain. And with so many so called “peripheral” devices placed directly on the motherboard, you could be changing out a lot more than you might think of.

Now, “it’s not always true” because there are certainly situations where it may not be necessary, but it really requires being on top of exactly what’s being replaced. If you were to replace a motherboard with the exact same kind of motherboard, a reinstall might not be necessary. Similarly, it’s possible that within certain motherboard families you can get away with not re-installing the operating system. Heck, it might even kinda sorta work with some boards that aren’t even related. But I sure wouldn’t want to bet on “kinda sorta” on my PCs.

It’s “usually half true” because technically you don’t have to reformat. Reinstall, yes, but the reformat is optional. You can install on top of the old hard disk’s contents if you like without the reformatting step.

It’s “practically true”, because if you’re going to reinstall anyway, it makes practical sense to clean up the hard drive with a reformat before you do so. Take advantage of the opportunity.

So my advice: I’d always plan on backing up, and then reformatting and reinstalling on a motherboard change, unless it was exactly the same motherboard.

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36 comments on “Must I reformat if I replace my motherboard?”

  1. I have done this several times and formatting and starting fresh is the best way, especially if you can add a new drive to the mix and increase drive space. Install the OS to the new drive and use the other one for additional space as a data drive.

    For people that just can’t start over, I have also had success with XP doing a repair installation. This loads the correct drivers for the new chipset so XP runs without having to reinstall all your programs. You may have to load some drivers seperately, like the intigrated network and sound cards, but this is true with a format, also. The advantage here is you can be back up and running in less than an hour.

  2. I was wondering about a certain issue I have realted to this. I want to replace my motherboard with one that uses more and better RAM (perhaps a new processors wouldn’t hurt either) I know that I must reformat the drive containing the o/s but I also have a larger drive I use for storage and most of my new programs/games and I wonder if I must reformat this one as well. I’ve downloaded alot of program updates for some and would prefer not to download them again though something tells me that attempting just a switch on the board and master drive will not be enough.

  3. You don’t need to reformat, if that drive is going to be the “second” drive. The only one I recommend reformatting is the one that the operating system will be installed on.

  4. hi,leo. i also met this problem and have formatted the harddrive on another machine by just right click and format. then i put the harddrive to the new motherboard, insert xp CD. when the blue screen showed up and asked me to choose enter , repair or quit(ESC)
    the computer shutdown itself (which happened also before I formatted the harddrive).
    did i format my old harddrive correctly?
    how to solve the problem?

  5. It is perfectly possible and also practically feasible to change the motherboard (and all the rest-CPU, memory, drives, etc.) without reinstalling Winblows. I have done it myself, and it worked.

    The proper way to do it is to go into the Hardware Devices manager and remove ALL of the “System devices” – BIOS, PCI and AGP bussess, memory controllers, everything. Also remove anything else that will be changed, maybe the video card and built-in USB ports? After you have done that, shut down and change the boards. When the system is started next time, Windows will discover all the new devices on the board and install proper drivers etc.

    It is also possible to move the Operating system to a completely new hardware, including the disk, which involves doing a full backup, installing Windows on the new drive, then restoring the backup on the new machine, but NOT restoring any hardware drivers. Microsoft Knowledge Base has few articles about these things.

    You are right, Leo, any opportunity to clean up the clutter Windows accumulates over time should not be missed. Fresh installs are always the best and fastest way.

  6. I have changed my motherboard on my pc which I built about 2 years ago. I also wanted to reformat my hardrive. I only have one HDD, it’s a 120 gb. I went through all the steps taken in doing so..I booted from cd-rom first, using the same windows XP CD I used to originally install XP and selected the NTFS file system. (There was also the option of doing this with the work “quick” next to it, but I wasn’t sure what this was used for so I selected the NTFS without quick) However, after the hardrive was reformated 100% the next screen said it failed and it might be due to a damaged hardrive. However my hard drive was not damaged before I changed the mother board. I am almost positive I didn’t cause any damage through static electricity or any other means. Can you please help me and tell me if it’s possible I made an error somewhere? Thank you, MIke.

  7. I have a problem along the lines of what is being discussed here. My sister’s motherboard fried so I replaced it. The post goes fine, memory seems ok, drives are detected, but now I get the “error loading operating system” and that’s as far as it goes. Her hard drive was working fine and she has a lot of pictures and things she would be pissed about losing. From what I read here if I use the XP cd to REPAIR the installation windows should update the new motherboard drivers and be functional again. Is this too good to be true??

  8. I replaced my processer and my MOBO , however I did not realize that any such hardware changes will cause this problem to my windows untill I did the change, so a repair did not work, after copying the files setup needed it will reboot the computer, and then it wont actually load into the windows setup (offcourse without pressing the anykey to boot from cd) it will load the windows which will obviously fail.

    Any suggestions?

  9. i need help. i just recently replaced my mother board, and i cannot reformat. i have my windows xp disk and i try to boot from CD-ROM drive, but it just says Booting from CD:_ and stays there forever and does not boot. i cannot reformat and i was wondering if i need to buy a new hard drive.

  10. i canot see the universal serial bus controller in the device manager and when i put any flash memory it doesn’t work what i can leo computer is p2 .

  11. Leo,

    I have a sony Viao that i purchased in 2001. It has a p4, 1.5ghz processor, 384mb SDRAM and lately it has been acting really slow gaming wise. Here’s the question: I also have a Emachines 1.9ghz AMD 2300+, with 128mb DDR….should i change out the motherboard so that i would be running off the emachines since it has better RAM and Speed or should i stay with the VIao for its Pentium 4?!

  12. I want to replace my motherboard. it is a D915GLVG chipset .Is it possible to replace it with a new one without changing the processor.

  13. i have just changed my motherboard and my processor, since doing this my pc wont boot up, it gets to where it would load windows and then restarts, HELP!!!

  14. Many of you will have to do a “Repair” from the XP CD. It still may not work correctly afterwards.

    You really have to PREPARE your system before you replace the motherboard. Changing the IDE drivers to standard, the video to standard is probably a good start. BACKING UP ALL YOUR DATA is also a must. If you don’t know how to back up your data, you have no business changing the motherboard.

  15. I replaced my motherboard and processor and I didn’t have a problem. Guess I was lucky. I even installed versions of windows on different hard drives plug the hard drive into a totally different computer and windows loads right up.

  16. my computer was given to me it run a bit then shut down . i cant get past the system starting up on the black screen for loading it ask for a bootdisk error please insert start up disk i dont have one what can i do………i cant even type commands wont even go to start up page……….

  17. I installed a new MOBO and have everything running, I have alot of files backed up on 2 other HDDs, They work and are recognized BUT XP would like to reformat them. I dont want that. Is there ANY way to not have to format the 2 HDDs?

  18. Just replaced the motherboard and processor. Went to do a reformat, but when we put the xp disc in, it goes through all the checks, but when you get to the first screen where you hit “Enter” to install, once you hit enter it just freezes and says “Please Wait…” at the bottom of the screen. We have tried several different known good sticks of ram, several known good hard drives, and cant seem to figure it out.

  19. I am soon to replace the motherboard and CPU. I just need to know whether or not i will need to do a complete re-format. I am asking because i have a pre-installed windows xp system thus i have no OS disk. This is a really great feature to have as i can put my computer back to purchase state whenever i want but i need to know if this will work when i have replaced the board and cpu. When i do the change over my computer will be back in its purchase state and so when i go to turn the pc back on it will go straight into xp setup. Will this work the same way as having to format and boot from an xp disk?

    Hash: SHA1

    Please read the article you just commented on. It addresses exactly that

    Version: GnuPG v1.4.6 (MingW32)


  21. I was pretty jazzed about the prospect of changing out my OEM motherboard. Shame on me, I bought a system without PCI-e. I believe many of us have OEM systems and they do not come with WIN XP CD. As I researched the issue I discovered that there is NO common ground among the “experts”. My IT rep said – “just drop that baby in and power it up – no need to do anything else” Yeah right. Too many conflicting opinions. My advice – for the faint of heart – save your bucks and get a new system that meets your needs. It’s pretty sad really, all the great board bundles out there – and you are stopped dead in your wide eyed tracks. No CD – NO upgrade.

  22. I remove my previours hard disk because it corrupt!!
    I buy a new one and reformat it with windows xp sp2, After loading everything form windows xp sp2, and comes to a state where Setup is Starting Windows, it stays there and won’t continue..can anyone HELP ME PLEASE!!!!

  23. Self-built system in December. Motherboard died last week. Warranty replaced the identical board. I installed it, and everything works fine…except the system will NOT shut down. Go to shut down, and it restarts everytime. Nothing in the log file…don’t know what to do.

  24. I built a new computer from scratch and installed windows xp pro OEM with sp3. The motherboard went crazy. I replaced with a totally different model. Can I reinstall that copy of windows?

  25. Hi. I am new to the whole computer building thing having only done one before. Working on a second build for a friend and have a lot more trouble than the first. His MoBo was zapped so i told him i could install a new one for him. Ended up installing the mobo and all his existing peripherals except cd-rom (had to get a Sata CD rom drive because his new motherboard didn’t have the Eida ports for the old one. Heres the problems… the board will not recognize the old hard drive in the bios. I figured whatever killed the old Mobo killed the Hrd Drive as well so we picked up a new WD caviar and installed it… still no luck. Am i Missing a step here or is possible the Eida port on the mobo dead? From reading the article i think maybe i need to format the disk. How Do i do that? Help please!

  26. What a waste of space this article is. All you’ve done Leo is sit on the fence and muddled the information on what you can and can’t do. Where’s the definitive YES or NO that people count on from the techs-for-hire? The answer is out there..the CLEAR answer. Fortunately I had it before I came here. Look elsewhere people and you will find it is possible.

    I disagree that there is a “clear” answer. (And why didn’t you share it, if it’s so clear?) Fact is it depends on the specifics of the situation.

    – Leo
  27. I’ve actually had some luck not reformatting. I got Windows XP Pro a few days after it came out. Shortly thereafter, I joined the military, moved away from home, and was sent over seas. Of course, I had my PC shipped to me, but alot of my disks were missing, including Windows XP.

    Long story short (Too late, I know) I decided it was time to upgrade my PC… Mobo, CPU, everything. Except I had 2 perfectly good hard drives! Went from a Socket A CPU to a 939, and an Acer Mobo to a MSI, then a Biostar a few months later. Windows… well, it wasn’t happy, I had to fix a ton of errors, but they were all either settings that needed to be set/reset/updated, or drivers to install. THEN, I went from that set up, to another Acer Board, with an Intel CPU. Again, worked, after I spent a while fixing it.

    Granted, it was a moot point, I only did it because I was bored waiting for Vista to arrive… but it did work.

    All told… 5 years, and 3 “Heart, soul, and brain” transplants, and even went from AMD to Intel. All because I couldn’t find my XP install disk! Its possible to not reinstall… I just don’t think its likely. I’m pretty sure I was exceptionally lucky each time.

  28. i just replaced my mother board with a a new one due to damage while shipping, i reformated my hard drive with windows vista, but now when i hook my air card up to the computer to get online, it will load the program, connect, then just shut off, and automatically load the program and it just keeps doing that, it will connect for 3 seconds then just cut off. could this be because of a bad install?

  29. Hello !!
    I want to change my Motherboard and upgrade RAM.Basically I want to updgrade my PC for gaming.
    The problem is that I currently I am Using Intel 865G motherboard and intel P4 2.60Ghz processor with 256MB ram, 865G supports DDR Ram, if I try to buy 1 GB DDR ram, its too costly, so somebody gave me idea to change the motherboard and opt for DDR 2 Ram which is very cheap, so I want to Know about the latest motherboard with Graphics card installed on it , which can use P4 2.60ghz process so that i need not buy new processor , can anybody guide me (OR tell me suitable motherboard) .. Thanks in Advance ..

  30. I have a question? i have bought a new motherboard. The old motherboard i had removed everything from the old motherboard and install it to the new motherboard. But when im done doing that when i turn on my computer would it take me straight to windows like normal or i have to do something else before like going to bios or something else?

  31. Hi this what you do when you buy a new motherboard makes shure that the old stuff be out of date when getting new baord check to see if it the video card supports and ram. if it do support or just put it in and turn on the pc go to bios change the boot drive to cd or dvd and put windows disk in and save bios setting boot from disk start installing the windows put your key in do the instuctions what says on cd if you using rad drive hit one of the key and add them in. Next reformatt the drive and it tells you what do when done installing your windos put in your motherboard drivers 4-1 other if you using on board sound or other features. Later could up date your motherboad drivers and and your video card drivers get the latest ones keep your pc update. That how you install windows All it’s so simple to do.

  32. Hi if you have problems that your pc runs slow when and having the lag or freeze that cause it is video card and windows XP needs 256 of ram that not include the games you install better 1 gig or more Vista and win 7 needs about 2 gig of ram to run better run a lot better if you put more ram better check to see if your motherboard supports more ram. When buy in a new hard drive or ram buy the bigest one cause they on sale look for the deals first. This tells you your games need ram or a better video card with ram on it like GTA,Call of Duty all,Unreal all,new programs read first when buy new Games Software need a lease 2.2. or 2.8 GHz the new stuff wants a lease 8 gig of room to install read first what you want to do with your Computer. The Shellshock2 needs 3GHz or larger single core processor.

  33. I just bought a new battery for my laptop and but it doesn’t charge up. Dell tells me since my AC adaptor is working properly, it may be my motherboard that is not “recognizing” my new batter for charging. They recommend that I replace my motherboard. That’s costly for me at this time. Plus, I may also lose my data in the process. What should I do?

  34. i have a kinda fast pc im think bwt changing the mother board so it can support more than 4 G ram and a newer CPU(i3 or i5) wt would u guys recommend ?


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