Yep, you are hosed. Wiping utilities usually display a warning that this very thing will happen. From the utility's perspective, data is data, it does not look for OS files to spare them, all data is overwritten. If you're lucky you can get a copy of Win7 from someone to use, but you will probably have to purchase a new license key. You will also have to go to HP's site to get the drivers for the 6910p. It was a very popular business-class model, so the drivers will be available.