If I buy...

A new Motherboard, CPU, GPU, PSU, RAM, but keep the HD I have now and use it with all these new components, what will happen with my OS. Will I still be able to turn on the comp login and have everything the way it was before but with the better performance from the new hardware? Or will I have to go through the whole installing windows again process.

If I do have to install windows again, what should I do if I have lost my W7 disk?

It may or may not work. I have replaced a MB and CPU and Video Card and had it work. I had to re-activate the OS It would not re-activate via the internet so a phone call to MS is all it took explained the situation they give you some numbers and letters to insert and they take you through it step by step. If you OS was full version and not a update it should hopefully work

And I've had it not work and had to do a fresh clean reinstall and still had to call and do the what Super Sarge said.

Good luck! It sounds like you will have e a better machine.

If you replace the motherboard and the CPU it's always best to do a fresh clean install. You'll probably have different chipsets on the motherboard that need different drivers. Also you're putting in a new video card. Basically, you've built a new computer so therefore a new install in necessary.

Did you lose your Windows 7 install DVD? Do you still have the C.O.A with the product key? If so you can download a legitimate copy of Windows 7 in ISO format and burn it to a blank DVD. IF you don't have the C.O.A. with product key then download S.I.W. (System Info for Windows) as a standalone program. When you run it there's a section in the far left window column called Licenses, click on it and it will show the Windows 7 key you used when you installed it the first time.

here comes digerati !

If your copy of Windows came originally preinstalled on a computer then it's likely an OEM license, which doesn't allow you to continue using it on a new computer (a new motherboard = new computer as far as Microsoft is concerned). So if this is the case you'd need to buy a new retail copy of Windows 7 in order to comply with M$'s licensing.

If you replace Motherboard, CPU, GPU, PSU, RAM with the same specs it will still work

Why wait for me when you know the facts too. It is the message that is important, not the messenger.

And the message is this - IF your original license of Windows is an OEM license, it is tied to the original computer and cannot legally be transferred to a new computer. And understand a new motherboard is considered a new computer.

Note the following:

Microsoft Knowledge Base Article 824125, near the bottom under More Information (my bold added),

Quote:

Users who run a Microsoft Original Equipment Manufacturer (OEM) operating system may upgrade or replace most of the hardware components on the computer and still maintain the license for the original Microsoft OEM operating system software provided by the OEM, with the exception of an upgrade or a replacement of the motherboard. An upgrade or a replacement of the motherboard is considered to create a new personal computer. Therefore, Microsoft OEM operating system software cannot be transferred from another computer. If the motherboard is upgraded or replaced for reasons other than a defect then a new computer is created, and a new operating system license is required. If the motherboard is replaced because of a defect, the user does not need to acquire a new operating system license for the computer. The motherboard replacement must be the same make and model, or the same manufacturer’s replacement or equivalent, as defined by that manufacturer’s warranty.

Microsoft OEM Licensing FAQ, under System Builder Licensing, 8th Q&A,

Quote:

Q. Can a PC with an OEM Windows operating system have its motherboard upgraded and keep the same license? What if it was replaced because it was defective? A. Generally, an end user can upgrade or replace all of the hardware components on a computer—except the motherboard—and still retain the license for the original Microsoft OEM operating system software. If the motherboard is upgraded or replaced for reasons other than a defect, then a new computer has been created. Microsoft OEM operating system software cannot be transferred to the new computer, and the license of new operating system software is required. If the motherboard is replaced because it is defective, you do not need to acquire a new operating system license for the PC as long as the replacement motherboard is the same make/model or the same manufacturer's replacement/equivalent, as defined by the manufacturer's warranty. The reason for this licensing rule primarily relates to the End User Software License Terms and the support of the software covered by that End User Software License Terms. The End User Software License Terms is a set of usage rights granted to the end user by the PC manufacturer and relates only to rights for that software as installed on that particular PC. The system builder is required to support the software on the original PC. Understanding that end users, over time, upgrade their PCs with different components, Microsoft needed to have one base component "left standing" that would still define the original PC. Since the motherboard contains the CPU and is the "heart and soul" of the PC, when the motherboard is replaced (for reasons other than defect) a new PC is essentially created. The original system builder did not manufacture this new PC, and therefore cannot be expected to support it.

For more information about the differences between OEM and full retail licenses, see this FAQ and note question 11.

I understand that is counter to what many have believed, but it has always been this way - read your EULAs. OEM - Original Equipment Manufacturing - licenses are for just that, "Original Equipment". It is important to note too that OEM versions are sold at substantial discounts. If transferability is important, you must buy a full retail version.

If you have purchased other software, it may not be transferable either. The exception for Windows is IF your current version is a "retail" full (not upgrade) copy, and you completely remove it from the old computer.

So, to be clear, if your current version of Windows is an OEM (also called "System Builders") version of Windows that came with or was purchased for your old computer/motherboard, you cannot legally transfer that license to your new computer. This applies to Upgrade licenses too as they are directly tied to the license they are upgrading. This means you cannot install it (or the old drive it is currently install on) on the computer with the new motherboard.

NOTE - While technically, installing an OEM version on a new computer can be done, it is NOT legal and is considered stealing. This applies to computers used in the United States, member countries of the EU, and member countries of the United Nations. Check your EULA. In all cases, it will say something similar to this seen for Windows 7 Professional, (their bold), It is important to note you do not own the software, you own a license to use it. And by using it, you agree to the terms of the license.

Note this is an industry policy, not just Microsoft's. And please note, I am just the messenger!

Please note that even MS does not always follow this policy, I replaced an MB and CPU different in both cases I stuck my HD in booted and had to activate Windows (it was Vista OEM version) again it would not automatically activate, I then called MS as per the the instructions given. I told them what I had done they asked a few questions I answered them, they gave me a set of numbers to insert, they took me through it step by step my machine activated. This was an OEM version of Vista.
Maybe I go lucky but I know this did happen as it happened to me.

Well our poster has not stated their version is oem but they have been informed in case it is.

Whether a Microsoft rep allows it or not does not make it correct per the license agreement so please read your license agreement.