Most gpu provide the requirements for their operation either on the box or the support website. IMO, you're OK. However, since the PSU has already provided a service, the wear&tear have already done some damage, though not apparent. In other words, it always helps to have more PSU than you need, besides wattage the amps as well. Newer released gpu's of the same series, tend to be less power hungry, so you may luck out, but verify by reviewing the specs. For now install new gpu and test results proceed as required.
I'm going to upgrade my graphics card from a gtx 550 ti to a gtx 570 and was wondering if I need a new power source. The gtx 570 calls for a 550w supply. I currently have a 750w, but was wondering if this was enough when the other components of my computer were factored in. Any help would be greatly appreciated!
i5 2500k win 7 gtx 550 ti 8 gig RAM Corsair 750 power supply

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