It shouldn't be like that. I never heard of it too.
I had best results if using at least half of BCLK frequency for PCI-E when I get over 200MHz BCLK (I ran 230 BCLK with 115 PCI-E without Slow Mode).
It is so cheap, I would try.You can get it and then choose better one, right? It is higher binned, but it doesn't necessarily means it will OC better.
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