I have one working perfectly fine in a Shuttle SN95G5 O/Cd to 2520 (280HTT limit in BIOS). But seriously, stock? That's not what Opterons should be for
You can get around the BIOS limitation with ClockGen, and the 240W PSU should be enough for most things (currently running X800XL + 2 HDDs + Optical)
If you want more information about Shuttle SFF, either read SFF section of AT or go to
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