On Sun, Nov 16, 2008 at 04:34:28PM +0000, Srdjan Todorovic wrote:
Hi
2008/11/16 Chris G cl@isbd.net:
came with a 355 watt power supply so I though I might as well use that and keep the ordered (430 watt) one as a spare. I built the system and it worked OK until I added a second SATA drive, or at least I saw the same symptom a few times with only one SATA drive but put it down to misconfiguration. However when I tried to get it going with two drives it always just powered up for two or three seconds and then powered down again. A bit of searching suggested that it *might* be a power supply problem and so it was, using the 430 watt supply instead has made it work perfectly. Amazing that a system which idles at 50 watts and always uses less than 100 watts can't start up with a 355 watt power supply. Apparently SATA drives hit the 12 volt rail harder than IDE drives used to.
Really? How? Why? I seem to remember reading that my Western Digital 500GB 7200rpm SATA drives use 6W each. And this AFAIK was from the datasheet/specs from WDC.
That's what I'd have though too but it was fine with two IDE drives and a SATA drive, it was just two SATA drives together that caused problems.
Is 6W really that much of a difference to cause this problem?
I think it's the startup current rather than the steady state.
Surely it's probably due to a rubbish unbranded PSU with badly rated/cheap components? What make is it?
If you hunt around using Google you come across quite a few people who have had problems with multiple SATA drive and various branded and other power supplies.
Yes, it was a 'generic' cheap power supply but it was the SATA drives that tipped it over the edge. The one that worked cost less than £10, hardly 'top notch'!