Cheap ones don't last forever. I've gone through three, but the current one (not cheap) is going on 7+ years.

You can put a wattmeter on your PC to see how much power it really needs while rendering. People are usually surprised at how little is actually consumed.

You can put a wattmeter on your PC to see how much power it really needs while rendering. People are usually surprised at how little is actually consumed. I actually did this a few years ago when I was documenting the power consumption of every single thing in my house.

My computer:

Intel i7-965 Extreme CPU 3.2GHz, 700 Watt power supply, ASUS P6T-Deluxe motherboard

Power consumption in idle state (no apps running): 185 watts
Power consumption with all 8 cores running 100%: 300 watts

The power increase may not seem like much, but since it's concentrated into that little CPU chip, the temperature increase is huge, going from 48 degrees C, to over 80 degrees.

My conclusion: for my system, a 700 watt power supply is probably a little larger than I need, but the seven cooling fans in my custom case are all very important.

I would agree your power supply is likely gone.

Not saying you had a cheap power supply but similar to what riredale is saying, there can be other issues with cheap power supplies having ripple or surges on the outputs. While a system make work with them, I have found those systems to be unstable/fragile.

"Since my guru is in the hospital with both his feet amputated my source of info is lacking..."

I'm more interested in what the heck this opening sentence is about. Both feet amputated?!?

Gee, and I thought it was an expensive one. Shows you how far out of the loop I am.
I think it was about 150 dollars. With the Ebola possibly moving to Cleveland I sure hope none of that stuff gets on my new power supply.
JJK

It's already here in Dallas. (sigh)

$150 is not a cheap one. I guess it was just bad luck then... If you wanted, you could probably take it to a TV repair place and get it fixed. It would probably cost more to fix than a new one but likely less than $150.

Intel i7-965 Extreme CPU 3.2GHz, 700 Watt power supply, ASUS P6T-Deluxe motherboard

But what about your optical drives? For instance if you have two and are making a copy .. both are running. How much does that add to your load?

But what about your optical drives? For instance if you have two and are making a copy .. both are running. How much does that add to your load?I didn't measure this, but I did measure the additional consumption of a hard disk drive by adding a full-sized SATA drive to one of the removable bays. Additional power draw: 7 watts.

Here's a site which provides some useful measurements, and they confirm my initial measurements, although their numbers suggest that the optical drive power consumption might be closer to 25 watts. I am a little surprised that it would be that much, but all the other numbers seem to be correct, so I guess this is probably the right number.

Power Consumption of PC Components in Watts

Even with two of them reading/writing, the total incremental load would be less than 50 watts, still leaving me at less than 50% of the power supply's rating.

Some people suggest getting huge power supplies, but as an electrical engineer, these recommendations have always seemed to be based more on urban legend than actual engineering calculation.