Re: GTX 280 screeching...
Seeing the number of people that are experiencing this issue, I don't think it's damaging to the card. A new PSU fixed the problem for me but I bought it for other reasons and did not expect it to help in that respect.
The PSU switch works in certain cases, and doesn't in others, regardless of wattage. I still think it has to do with how the PSU was made - that is you're probably more likely to fix it with a higher priced unit designed for higher loads.
But still at this point it seems to be hit or miss, so If you're in the market for a new PSU, then fixing the screeching could be an added benefit but I wouldn't throw down $200-$300 just because of it.
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