None of the usb ports work on my ASUS Z97-A motherboard, the mouse and keyboard were able to work in 2 of them for half a windows installation but now none of them work, they power on my mouse and keyboard but I cant get a signal, I've tried with multiple keyboards and mice, the case ports aren't working either, The 3rd and 4th Dimm slots arent working either of that's helpful. Anyone had this problem?
We will need more information. Can you list your specs like so:
Which OS are you trying to install? Mention the age of your PSU and can you recall which BIOS version the motherboard is/was on?
You might want to try and breadboard the system with just one stick of ram and with the iGPU, remove the CMOS battery(while the entire system is powered down and switched off from the mains) and replace the battery after 30 mins.