Changed graphics card, now imac turning off when playing HQ games

[dominic1444]

Hi



I changed the graphics card in my late 2009 iMac to the 6970m 2gb card.



It all works fine until I start playing a game on steam. This is a very high-quality game and I would imagine that it would take up a lot of power.



The problem I have is that when in-game, the iMac will turn off after about 2 minutes of gameplay. This will keep happening every time I try to play the game.



Any help would be greatly appreciated.



Thanks

 

[Georgio]

Sounds like a heat issue. All well and good changing the card but if the power supply can't keep up the Mac will shut down to protect itself.

 

[dominic1444]

Sounds like a heat issue. All well and good changing the card but if the power supply can't keep up the Mac will shut down to protect itself.

I don't believe this to be a heat issue as I can keep the computer on all day with no failure but only when playing games it shuts down.

There have also been many people changing to this type of graphics card.

 

[Georgio]

Yep but there is a world of difference between your computer idling and playing games. It will either be heat build up tripping a thermal shutdown or the card draining more power than the PSU can supply also causing a shut down.

 

[elf69]

does sound like the GPU is drawing too much power under load.

Normal day to day use is low draw.

if heat is within the cooling efficiency of the head sink and fan then I do not know if bigger PSU is available for imacs like a normal tower pc

 

[dominic1444]

I will install some component temperature monitoring software to see if it does spike when i play the game.

 

[Georgio]

Either that or try and find out what the rating is for the PSU in your Mac, then look up what the power requirements are for the card you've installed under load.

You have to bear in mind that any manufacturer will probably not build in any head room into the machine's power spec 'just incase' the owner wants to upgrade the machine later. This is more true of Macs more than PC's as Apple ultimately want you to use it and then upgrade to their 'new' machine a few years later.