The 5570 calls for a 350w unit, just like the 7750. The 6570 calls for an even higher 400w unit. What you need is a different PSU, not a different graphics card. You're going to end up selling yourself short and probably end up getting something that kills your low end PSU anyhow. Save your money until you can get the PSU, and get IT first. Then get the card so you can be sure you will have an adequate PSU and not damage either the PSU or your card, or even your motherboard.
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