What can happen if I don't supply enough power to my graphics card?

[bejamartins]

I know the basic answer is "it won't work", thing is, just realised my old graphics card was using a less powerful than minimal reccomended power source (I had a 650W source and NVIDIA states that at least 680W power source is needed.

 

Could this have damaged the card? (It overheats even clean and with thermal paste replaced).

[Comessy]

Nothing will happen. They put those recommendations with a massive margin of safety. 

[Aniallation]

I know the basic answer is "it won't work", thing is, just realised my old graphics card was using a less powerful than minimal reccomended power source (I had a 650W source and NVIDIA states that at least 680W power source is needed.

 

Could this have damaged the card? (It overheats even clean and with thermal paste replaced).

No. A card that "recommends" 680W PSU in an average system will only see at most 500W of max total power draw.

[19_blackie_73]

if your psu does not deliver the needed power, it'll go up in smoke or switch itself of, nothing will happen.

I run my 970 (recommended 550W) on a 500W PSU and it uses only half of the power (cpu AND gpu maxed out ~250W)

[Tech_Dreamer]

Actually the real world power draw from the wall is around 500 watts maximum on a single GPU system on a top tier system, only thing you need to pay attention is that if you do uber water cooling & triple SLI or cross you gonna need more than the usual 500 watts , actual test show  an nvidia flagship GPU can run on load pretty much under 500 watts

 

i think it was TTL's video that showed the actual tests on this , But Mind you if you use an R9 295x2 you're gonna need atleast a 1000watts PSU, power draw on just those GPU have been upto 700+ watts for the GPU alone!! fo rnvidia & your specific GPU that PSU  wattage is more than enough, it's just the recommended safety margin..

[Aniallation]

But Mind you if you use an R9 295x2 you're gonna need atleast a 1000watts PSU, power draw on just those GPU have been upto 700+ watts for the GPU alone!! 

Where did you hear this??? 295X2 power consumption is around 700W for the entire system

 

 

 

 

[bejamartins]

I see.

So you guys think if I try it on a more powerful source it would not have a temperature improvement as is?

[Eugene Yap]

It would just crash. Lower quality PSU would just overload and burn out, sometimes ruin you the rest of the components if you are unlucky

[Eugene Yap]

I see.

So you guys think if I try it on a more powerful source it would not have a temperature improvement as is?

Yes, just the PSU.