Use a 2nd power supply for graphics cards?

[huskyxx]

My power supply is just not enough. i have 4 R9 290s on a 1200 watt. When i take the cards up to 1000 gpu e / 1500 memclock the system goes kaput. 3 cards at those settings work and also 4 cards at 860gpu/1250 memclock work. So i'm fairly certain its not enough power.

Can i use an old CPU's 700w power supply to give the graphics cards additional power?  I'd have to mix power supplies per card, so one of my r9 290 cards would have some power coming from the 1200w and some power coming from 700w.

is this a horrible idea or feasible?

[PondSea]

Never mix power supplies. Just buy a bigger power supply to power 2 cards or something.

[Echoenigma]

Never mix power supplies. Just buy a bigger power supply to power 2 cards or something.

Why never mix power supplies? This is what I was planning on doing, what is wrong with using 2 psus?

[cozk]

Never mix power supplies. Just buy a bigger power supply to power 2 cards or something.

You are officially retarded.

Why spread misinformation ?

For multiple PSU : google add2psu

[SgtSpike]

Never mix power supplies. Just buy a bigger power supply to power 2 cards or something.

Why never mix power supplies? This is what I was planning on doing, what is wrong with using 2 psus?

Well, potentially, they could put out slightly different voltages and destroy your hardware.  But many people do it without ill effect.  I'd go for it if it were me.

[Wipeout2097]

Never mix power supplies. Just buy a bigger power supply to power 2 cards or something.

You are officially retarded.

Why spread misinformation ?

For multiple PSU : google add2psu

Nowhere he is counter-arguing against using 2 PSUs per se. He is mainly against the OP's usage of power for the same card(s) coming from different PSUs.

Understand the context before you throw random insults around.