Do I need a new PSU?

Been having trouble with a couple of hard disks, two 500 gb Seagates. Their SMART status is showing fine and not tripped. But one attribute is troubling me. It is Command Timeout (188) is not zero on both drives. Googling suggests cabling/device or PSU. I have changed the cables and so far so good but they are still getting the odd counter increase.

The disks are nearly two years old and a Hitachi I have just bought does not have this counter so cant compare. The PSU a Hiper 530W is about 4 years old now. I was thinking of replacing it with a Corsair 500W and while I'm at it the same for my other machine downstairs which has a WinPower PSU which are known to go pop after 6 months. New PSU?

Ok went and changed them. All voltages are according to speedfan accurate. Before the 12v rail was showing 12.24v and now with the Corsair its showing 12.03v and all other voltages are around their nominal. Dont know if this will make any difference to the hard disks. Time will tell.

download a program called prime95

set it to max heat and stress test

it will murder your psu

get a volt meter into one of your molex connectors and monitor 12v rail

anything under 11.8 or above 12.2 then it will be unstable

Thanks Stan I'll try that on my new Corsair PSU.