Well I just got a new PSU and when I plug my main hd on it the computer starts but the screens don't turn on and I have a solid red light next to the battery symbol on my pc's front panel. If I disconnect it, everything works fine. All I have plugged are another hd and a cd-rom. I can't figure out if the problem is from the PSU or the hard drive itself.

If I use my old PSU everything works fine, including the main hd

Anyone has an idea on what the problem could be?