System goes down as new drives is plugged in to power

estoy

Distinguished
Jul 12, 2010
5
0
18,510
Hello,
I have an old system that works fine but I want to use a bigger HDD. The system boots with the old one but it refuses to even load the BIOS with the new one. Even if I do not connect the data cable it behaves like this as long as the power cable is connected to the HDD. If I unplug the disk from the power the machine starts booting but if I plug it in again the system immediately dies. This can be repeated forever. The old disk is removed when I do this. Now, the old disk (IBM Deskstar) requires 0.3A at 5V and the new one (WD Caviar Blue) 0.65A. I don't see that this small difference could be the cause of the problem. The machine has no power hungry devices connected. I have had the WD replaced to make sure that it was not just a bad specimen but the result is the same with the replacements.

What can I be missing here? Any help is much appreciated.
 

estoy

Distinguished
Jul 12, 2010
5
0
18,510
Hi. I've already tried this but to no avail. But as I say in the original post I don't even have to plug in the new disk to the IDE cable. As soon as I plug into the power cord the system dives and if I remove the disk it goes up again. (I assume that doing this with a live system isn't a good idea but ran out of things to try :))
 

gtvr

Distinguished
Jun 13, 2009
1,166
0
19,460
Well that sounds like a power supply problem. I would think if the ONLY connection is PS -> disk, and that kills things, it's the PS.

Did you boot with the disk attached? Not sure if plugging in after boot is a good idea though
 

estoy

Distinguished
Jul 12, 2010
5
0
18,510


Yes. The first thing I tried was to remove the old disk and install the new one and power up the machine the normal way. You hear the fans starting and the screen flickers but then nothing happens and the screen goes back to standby mode. (If I then pull the power plug on the disk the system starts its self test and boot sequence, and if I have a CD in it will boot from that without problem).

If I do exactly the same thing with my old disk the systems boots like it's supposed to. That's the strange thing and that's why I first thought it can't be the power supply, it must be the new disk. But replacing the new disk with another one just like it did not help either. So I'm stuck.
 
The power supply should have different cables going to the drives, one cable would have several power connectors. It's a long shot, but are the drives that are causing the non-boot state use the same cable for power? Maybe try a different cable set?
 

estoy

Distinguished
Jul 12, 2010
5
0
18,510


I've used the same one for the old and the new disk. And just to be sure I tried another one for the new disk. Makes no difference.