Can you use a 450watt psu if you have 300watt psu?

Jakg

andy2004 wrote: »

jeese,

well ebuyer have this http://www.ebuyer.com/product/102994 for £24.99
and i recently due to my 450watt psu that came with my pc case so therefore under warranty had a upgrade to a 550watt, the same as my sister bought for her's, which i was sent to get
replaced my sisters 450watt with one of these,
http://www.novatech.co.uk/novatech/specpage.html?NOV-PSU550 £21.85, sister got her's for £18 at the time. price has gone up slightly
how good are they, replaced 2 years ago on my sisters computer, and so damn quiet, but her system was, had to double check it was actually running thats how quiet.

Ah - you said Decent. Doesn't look decent...

andy2004 wrote: »

branded as Ebuyer Extra Value, so its not branded, but according to the posts its a good PSU.
the other PSU the one i got is a WIN Power but thats because Novatech sell that brand as there own, its a generic PSU.

eBuyer filter reviews, and usually user reviews are rubbish anyway - a lot of the good reviews are "z0mg my PC runs faster now" etc which are totally useless...

Taffybiker

As a general rule, fitting a higher wattage PSU than needed will be more reliable and last longer. If your system requires 300W and you fit a 300W supply it will work but will also be running flat out a lot of the time. Only the highest quality PSU's will survive for any length of time, and they are naturally more expensive. The cheaper ones will generate heat which will eventually destroy it, and perhaps other components too. Many motherboards have had to be replaced because of poor quality or under-rated PSU's. They are also sometimes the cause of seemingly unrelated faults: intermittent system restarts for example.
My advice is therefore to buy a branded PSU rated higher than necessary. It runs cooler and allows for expansion.

For laptops, I would stick to the rated voltage when possible. 20V in place of 19V would not hurt much, but the internal regulation still has to "waste" that extra voltage somewhere - again this turns to heat. As for the current, anything equal to or higher than stated is fine, but as for desktops, if it is higher it will most likely run cooler and last longer.