I have a Dell Optiplex gx520 and for weeks I was frustrated trying to get windows 7 installed. I tried a variety of methods and called Dell no less than 5 times and they insist it is impossible to do. Nothing is impossible I always say and sure enough, I figured out a few ways to do it. Right now I am getting a writeup of the process ready for some self help sites and wanted to branch out the process if I can to help more people in one shot.
The premise is this- you have a computer which has the hardware specs to run windows 7 (at least 1Ghz x86 or x64 processor with at least 1gig of installed RAM) yet each time you try some error prevents the installation from completing and you end up back at XP. Post here or PM me the computer setup you are running and what happens when you try to install windows 7 and what fixes you've tried in the past and I will see if I can help you. If successful I will update the thread over in the hacker forum for future uses.
If anyone has a dell like mine there are a couple pretty easy ways to get windows7 installed, depending on what OS you are running now. The easiest is to download an image of win7 from digital river winrar and some kind of partition editor (I like minitool for windows) and do the following:
First using the partition editor create a partition for the install (the size isn't all that important but at least 20gigs to be safe) and make sure to set flags Active and Primary.
Next copy the windows image you downloaded over to the partition you made and then using winrar extract the contents of the image onto the partition. Delete the image and you should have the contents of a windows7 install dvd on the partition and nothing else.
Find setup.exe and double click it to get the installer started, from there select custom install and point the installer to the new partition and from there when the computer restarts you should boot into the new installation, finish the installation and later on delete the old partition (the one running xp or whatever) and then expand the new partition to fill your hard drive (or whatever size you want)
For the sake of persistency once booted into the win7 environment it would be wise to make both a repair disk (just enter the word "repair" into the search box in your start menu and you should see the clickable "create a system repair disk" and then follow instructions) as well as a system image (searching "backup" should lead you to the backup and restore center, then click on "create system image" and follow instructions) and there you go.
If you want your computer to be as fast as possible, do this before doing any updating of the new windows 7 installation and as soon as you have both the repair disk and system image ready to go (make sure you get that system image off the hard drive and onto something external) wipe your hard drive and then reimage your computer with the system image you created using the repair disk you created/burned. (the process is super simple, after disk wipe put in the repair disk and select "restore your computer from a backup" or we and follow instructions so that you end up with a freshly wiped hard drive reimaged with the virgin win7 install you made before.
Obviously this write up is shitty but it's done on the fly, anyone with legit questions ask and I will help you out with whatever is fucking up.
I realize most people have nice new machines that have no problem running win7 but not everyone does and some of you prob have an older machine as a backup and might want win7 on there instead of xp.
Also if you try my method and cannot get setup.exe to run try right clicking and selecting "properties" and under the compatibility tab select run as administrator and look at the box "run in compatibility mode as" and see if you can select xp. You may only see vista, select it and close the properties editor and then try running the installer again and it should work.
The process is hardly ever seamless and easy, I spent three weeks figuring out how to get around dells piece of shit bios and missing drivers that prevented the installer from being able to access the hard drive. I am proud to have figured out what to do on my own and find this kinda shit pretty interesting so whatever problems ya'll have shoot, I'm all ears.