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

SkipClick

What good upgrade for the graphics card and the easiest way to ensure there is enough power to run my pc and everything else?. The PSU I have is 300 Watt but can I go a bit higher than this say 450 with out changing the psu? something like that? Graphic cards I'm looking at is Sapphire ATI Radeon HD4870 1GB and 21149-00-20R - 512MB Sapphire HD 4770 last Powercolor ATI Radeon HD 4870.

aerostar

If the PSU is rated at 300watts and you pull 450watts, it will either shut down/ go bang/ and/or blow your motherboard and components.

SkipClick

aerostar wrote: »

If the PSU is rated at 300watts and you pull 450watts, it will either shut down/ go bang/ and/or blow your motherboard and components.

Do I have to stick to the rated 300watts or lower?.

ktuludays

change the psu. they are not that expensive and this will give you better scope for your graphics card

timbim_2

Get a good name PSU, and if possible a modular one. Makes cable management so much easier.

DatabaseError

SkipClick wrote: »

...can I go a bit higher than this say 450 with out changing the psu? ...

erm.....I'm a little confused...you can't raise the power rating of a PSU witouth ...er...changing the PSU.

The PSU (Power Supply Unit) is a fairly big box, probably towards the top of your case, with lots of wires coming off it (your power cable from the mains plugs into it)
It is really easy to change...and 300w will certainly emit magic smoke if you plug a 4870 into it

Strider590

Bigger is better, overloading a low power PSU will likely result is permanent damage and data loss.

-TangleFoot-

I plugged a GeForce 6800GT into a Shuttle system with a 240W PSU once. It worked, but the system would sometimes overheat to such a degree that the power supply was too hot to touch! I think it might have killed a brand new hard disk drive at one point too...

With that in mind, I suggest you get the most powerful PSU you can afford from a reputable source. Here's a group test for you to pore over whilst you think about your budget.

DatabaseError

cheers, tanglefoot..they reviwed my main psu...I also have it's little brother..a 520w version, in another PC... a tagan in another..and er...something else probably unmentionable in the lowest spec PC (but much higher rated than required!) :P

WhichWayNow

On a similar note, how about Laptop power supplies?

I am currently using (a nearly non-working) one which has the following:
INPUT: 100-240V~1.3.06A
OUTPUT: 19V --- 4.74A

can I use another power supply with these stats?:
INPUT: 100-240V~,50-60Hz 1.7A
OUTPUT: 20V --- 3.25A

Edit: Just found this on the bottom of the laptop:
INPUT: 19V --- 4.74A(MAX)

andy2004

if your changing your PSU go for a minimum 550watt, you'll have plently of power for any new hdd drives etc that you want to add then. A decent 550 watt psu should cost around £25 maximum you can go for the expensive named brands, costing anything upto and including £100+,
My sister bought a 550watt for £20 at her local computer shop, its so damn quiet its annoying, compared to the 450watt i had <sounded like a tank, had to double check hers was turned on.
Your motherboard and devices will only use as much power as they need from the 550watt. So the wattage doesnt matter.