Somewhat OT - can underpowered power supplies damage a system?

[Thomas Cameron]

On 08/18/2010 02:36 AM, Suvayu Ali wrote:
> On Tuesday 17 August 2010 10:27 PM, Thomas Cameron wrote:
>> Say, hypothetically, I have 8 identical Intel DG45ID motherboard-based
>> system with 8GB memory and a single drive with a cheap-o generic 300w
>> power supply.
>
> That is seriously overloaded I would say! Every motherboard should draw
> about 40~60W depending on the CPU and RAM you have on each of them! In
> the past I have damaged hard drives by stressing the PSU. (I had too
> many drives on one cable)
>
> To keep stress on the PSU low, hardware review sites like Anandtech
> recommend running at the 60~80% mark of a PSU's power rating. That is
> the most efficient region for most PSU makes.
>
> I would recommend you to look at the ampere and voltage ratings for all
> the components you have, and calculate the needed power for the components.
>
> Power needed (W) = Ampere rating (A) x voltage rating (V)
>
> Also it is very important to not overload any of the particular rails.
> e.g. If one of the 12V rails for your PSU is rated at 120W then take
> care to put components such that the ampere ratings of all of them add
> up to 10A. (120W/12V = 10A)
>
> Hope this helps.
>

I've replaced all the PSUs with 500 watt units.  I was really more 
worried about whether I did any permanent damage to any of the system 
components.

TC