PCIE Gen 2 Can't find any device. Need help please!

[Aidanbbb]

My custom built computer ran perfectly but a fan was a tad loud so I entered the BIOS and set the fan speed to automatic or something and it ran at a slightly lower speed quite comfortably. Upon rebooting the pc it contains the startup menu black screen and says can't find any device with a flashing underscore. Windows is installed on my hdd and was previously working until now. I have removed the cmos battery and reset the jumper but still come across this error. I've checked all connections but nothing is helping. Any advice would be greatly appreciated. Thank you

 

[alexoiu]

Power off and connect the HDD to different SATA port.