You have probably heard this asked numerous times.
My laptop had a hardrive failure, I got a new hardrive installed and it worked fine.
Installed Windows 7 a day later, it worked fine also, before getting a blue screen.
I then leave thee laptop for a while, come back turn it on, and it cannot detect my HDD.
It proceeds to the install Windows 7 screen (W7 disc still in DVD-Drive) and when trying to do a clean install it shows up with No HDD to install windows to, and won't let me do anything.
I have A Dell Studio Laptop, and the type of HDD is oblivious to me.
I've been into the BIOS and restored it to default and putting the SATA controller settings to IDE and ASCHI? and neither worked.
Hard to say what you did the first time or what went wrong, so you may have no choice but to reinstall.
You should install with the drive set to ACHI. That will give you the best performance. In order to install Win 7, though, you'll need the RAID drivers, which you can get from downloads.
Sorry, I assumed you knew where to find downloads since you've already installed the operating system. Simply click Support above, then go to downloads, enter your model and operating system, and you'll find the drivers for your system. You need the Pre-OS install RAID drivers.