Many brand-name PCs, rather than giving you a regular Windows CD, give you a restore disc, which returns the laptop to factory configuration–junkware and all.

Just about the best thing you can do to pep up a brand-name PC’s performance is to do a clean Windows install. So here’s how to download a regular Windows CD so you can do just that, when needed.

And there’s one other situation where you’ll need this. If your PC came with 32-bit Windows and you want to upgrade to 64-bit, or it came with 64-bit and you need to downgrade to 32-bit for compatibility reasons, you can download the other version. The CD key for one will work with the other.

Here are links to the various Windows 7 versions from Digital River, Microsoft’s official download partner. All of them integrate Service Pack 1, which will save you considerable time the first couple of times you run Windows Update.

Windows 7 Home Premium x86  SP1 (bootable)

Windows  7  Home Premium x64 SP1 (bootable)

Windows 7 Professional x86 SP1 (bootable)

Windows 7 Professional x64 SP1 (bootable)

Windows 7 Ultimate x86 SP1 (bootable)

Windows 7 Ultimate X64 SP1 (bootable)

Also make sure you grab fciv.exe, which you can then use to check the file’s MD5. You can get the MD5 sums for the downloads at and if you’ve never used fciv.exe to check a file before, you can read my instructions on its use here. If the MD5 of your download matches the corresponding value on the web page, your download is good. If not, it’s either corrupt or it’s been tampered with. Since Digital River is Microsoft’s partner, an MD5 mismatch would most likely indicate a bad download.

Once the file is downloaded and you’ve verified its integrity, you can burn a DVD or create a bootable USB drive and install it. If you want to be really safe, after you copy it to USB, remove the ei.cfg file, which will then let you install any edition, including Home Starter. But make sure you install whatever version your computer has. The keys don’t distinguish between 32-bit and 64-bit but they do distinguish between editions.

Use the key on your computer’s certificate of authenticity when prompted during the install.