Windows 7 won't boot after erasing an old HD

Hello. I have a dell dimension 9100. I have two drives on it, a ~160gb drive that came with it with xp, and a 500gb drive with win7. I put the win7 in myself and had been using that. Finally, I decided to erase the old drive with xp on to install linux on it. After erasing the old drive, my computer won't start up. It says it cant find sata 1 or 3. I've tried switching the cables hooking up to it but that doesn't help. If I push continue after it tells me how it can't find them, it says 'loading pbr for descriptor 2...done' and stays there. I did not erase windows 7, I checked. Whats wrong? I erased the old drive so I could install ubuntu on it... I'm guessing since thats the drive the computer came with, I deleted the mbr... I have an external drive with ubuntu I can use to fix this. Before you say to use the windows install disk to fix it, I've already tried that. The repair utility doesn't scan and thus doesn't see my install.
The more I think about it, the more that it seems like its NOT an mbr thing. I think this because of the fact that the windows repair disk doesn't see any installation of windows.

The hard drive is not dead. I can read it via ubuntu. Sorry if this thread is hard to understand, I've copied and pasted on multiple forums
Heres the latest: Disabled all other sata's in the bios except the one the drive is plugged to. Now I no longer see sata3 not found or anything. After bios boot, it just shows a blinking cursor.

If you installed Win7 with XP plugged in then it wrote the Win7 boot files to XP to create the Dual Boot. To remove XP Mark Win7 Partition Active then run Startup Repair - Run up to 3 Separate Times until Win7 starts and holds its own System Active flags in Disk mgmt.

This almost always works with a few exceptions: If you have Win7 on a Logical partition it can't be marked Active until you convert it to Primary using free Partition Wizard bootable CD: How to set partition as Primary or Logical. Then rightclick Win7 partition to Modify>Set to Active, OK, Apply both steps. Run 3 Startup Repairs.

If any problems post back a camera snap of the maximized Partition wizard CD drive map and listings. Screenshots and Files - Upload and Post in Seven Forums - Windows 7 Forums

But I've already erased XP which is why my problem started... So how do I do any of these things without access to windows?

Did you read the blue links which are illustrated tutorials showing how to perfom each from the booted Installer or Repair CD System Recovery Options command Line.

Use Option Two to Mark Partition Active from Installer or Repair CD command Line.

Then from same booted Installer or Repair CD choose Startup Repair from Options List to run up to 3 separate times to write the System boot files completely to Win7 partitiion.

Yes so I suppose I do the active partition thing with the install disk, right? Then move onto the the 3 times thing with install disk?

Update: at list partition, I have two partitions; a 465gb extended and a 465gb logical... Is this right? In the photo on the guide it says primary...

BTW: the original drive that used to have XP on it is NOT plugged in... should it be?

This tells us you have a 465gb Logical Extended partition, which cannot accept the Active flag (and then the System boot files) without first converting it to Primary.

So you'll need to burn the Partition Wizard boot CD, boot it to follow the steps How to set partition as Primary, followed by How to Set Active partition -Partition Wizard Video Help.

You may need to reboot into PW after the first step in order to do the second, but you can first try them in sequence before clicking Apply.

Once you see the partition is now Primary Active, boot into Win7 installer to run the 3 Startup Repairs with reboots checking if it starts in between each.

Ok but will this erase my data? If so, I don't see the difference of this and just reinstalling... and which partition do I make primary since theres two 465gb partitions...

No it will not erase your data. This also takes minutes vs. hours for reinstalling. But if you have issues now may be a good time for Clean Reinstall if you want one. Do you need to rescue data?

What size is your HD - 500gb? The Extended is usually the same partition as the Logical, just listed twice as such.

You can confirm this when you boot into Partition Wizard by looking at the drive map. Is it one 465gb partition?

IT WORKED! YOU'RE AWESOME THANKS SO MUCH. This will be my go to forum from now on for win7 issues. None of the others forums helped. <3 <3 <3