I'm considering buying a XFX/Sapphire Radeon 6870. I have an OCZ StealthXStream 700W PSU, which has been fine for the last three years or so with my Radeon 4870 (512MB), but in checking the AMD certified PSUs today, the StealthXStream isn't listed. All I can see are the GameXStream and the EliteXStream.
I'm just wondering if my PSU will in fact be safe with the 6870 or is there good reason for the StealthXStream not being listed?
With powersupplies it is always a matter of risk. In most cases even really cheap ones perform fine as long as you dont go beyond 70-85% of its rating. But the cheaper/worse it is, the bigger the risk it will suddenly go poof. And there is always a risk it takes something with it.
There is also a chance it will cause other components to wear out faster, not to mention make it harder to overclock things.
In short, you choose how much money you spend on your power supply, 700W should be enough for that GPU, even with some room to spare.
Can you suggest any software that will measure the wattage my machine is currently using? In building the computer I was very finicky in making sure my hardware didn't exceed the 700W before buying anything, but I don't have any idea how much headroom I have for the 6870.
I believe the 6870 uses around 250W on load, which would be 100W more than the 4870.
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