Well, I've been working on this for a couple of days now, and I've researched this issue like crazy, but nothing I've found covers my situation, so I'm looking for some advanced help, please. I'm trying to perform a clean (custom) install of Windows 7 Pro 64-bit from the original retail DVD (not SP1). The main symptom is that I keep running into the error message: "Windows cannot be installed to Disk 0 Partition x". Now, as I said, I've researched the hell out of this issue, so I doubt I'm making any newbie mistake, but nothing I've found works. I've had frequent problems with the Windows installer creating it's special "system" partitions (~ 100-120 MB) wherever it felt like it, including on drives other than the desired system disk! So after extreme frustration with this, I simply removed ALL other drives except for the DVD-ROM and ONE 320 GB hard drive. Here's a list of things I've tried that haven't worked...Make sure the drive is not only empty of partitions, but is completely uninitialized: Doesn't help.I kept getting the horrific "EMS Boot" option after each failure (about which more below), and I've learned that whenever that happens, I will always get the same "Windows cannot be installed to Disk 0..." error. So in order to try to kill the damned EMS thing, I've been forced to completely overwrite the drive with zeros! I've tried just zeroing the first 10 sectors with the disk editor part of Acronis Disk Director 11 Advanced Workstation (bootable), but for some reason that doesn't always eliminate the EMS data. But even after erasing the entire disk to successfully eliminate the EMS Boot, the main problem always recurs.My system BIOS (ASUS Z87-A, latest BIOS) recognizes my hard drive perfectly well, so I don't need to load any drivers during the partition creation. Even so, I've tried loading the correct drivers anyway (and I'm not such a newbie that I needed to be reminded to replace the install disk afterwards! Besides, I loaded them from a flash drive). Doesn't help.I've tried setting the BIOS to either AHCI and RAID (eventually, the system disk will be a RAID 0 array). Doesn't help.I always let Windows create the new system partition and it's special ~100-120 MB partitions itself. Doesn't help.General system config info: Mobo: Asus Z87-A / CPU: Intel i7-4770K / RAM: 16GB DDR-3-2400 / Disk: WD 320GB SATA-II Now, one time the install worked perfectly to my new RAID-0 array of 2 WD VelociRaptor 10Krpm drives, but after the install was completed successfully, one of the two drives kept failing SMART tests and just died (it was very close to DOA when I got them the other day). I had to delete that RAID array and then remove them both from my computer. That was the first and last time I was able to install Windows 7 correctly. Finally, I'd also desperately like to ask if anyone knows exactly where the despicable "EMS Boot" data is stored, and how the Windows 7 installer knows it's there! I know you can disable the EMS Boot after Windows 7 is fully installed (with MSCONFIG), but that's no help at all when you're trying to delete it before every clean install attempt! How can I erase that stuff without erasing the entire drive? Does anyone know? Thanks for all your help!