This is a problem I have been having off and on for a while. I have a SR2173WM not original I have a the original 180gb Serial hard drive with Windows Vista I have installed 120gb with Suse 10.2 and a 40gb with Windows XP Plus the original card reader 1 DVD CD reader 1 DVD/rw Plus I installed a ATI pci express video card. The problem at first was it would never boot to the PCI express card I updated the bio's and I set the MB to default to the PCI card and off and on it would boot to the PCI card others not. Well that problem seemed to fade away and another came up. that is the MB flashes the CD roms and you can see the hard drive light come on and that's it the monitor never powers up. At first you could turn it off by the power button and then re-power it back up and it would come on. Then after awhile that didn't work, so I disconnected all the drives including the Cd roms except I left the serial drive connected it did boot up I then reconnected the 120gb and the 40gb drives and it still came on I connected the DVD rw and to my surprise it still booted up for a short time again. And it started again this time the only way it seemed to boot if I injected the CD tray (I still have the one CD connected) and three hard drives, the card reader is disconnected still. By opening the tray it would boot to the bootloader screen which is where I go all the time as it lets me decide which system I want to run. Now once again it will not boot, I can tell when it will boot and when not, because if it's going to start the MB will flash my keyboard twice the first time when it flashes the CD rom and then when it starts the keyboard come on and stays on. Right now I have the one flash with the CD rom and thats it after a while the hard drive light goes out and then there is darkness. Has any one got a clue? I thought power supply but with only the three hard drives and the one CD oh and two fans on the case I am not sure. I have tried to disconnect everything again but it still boots to a black screen.