You can possibly overclock the 9800 SE to 9800 Pro speeds with RadClocker but the differences between the 2 cards are more than just pure clock speed so the performance won't be anywhere near the same. I can't recall the exact differences but it's along the lines of 128-bit vs 256-bit, 4 pipelines vs 8 pipelines, lower clock, etc.
Oh, and welcome to TIMO!
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