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I built a small server for internal use. By mistake I bought 16GB of registered RAM.

The system now does not boot, I can only hear 1 long beep followed by 2 short beeps. The specification list of my moherboard claims that it only supports UDIMM modules.

Is RDIMM RAM not compatible with UDIMM slots or is it possible to run it in "compatibility" mode (as it happens for example with ECC RAM when used in motherboards that do not support ECC--ECC checks are simply disabled)?

If RDIMM RAM cannot be used in UDIMM slots I can be sure that those beeps signal a memory problem, otherwise I'll have to investigate some more.


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up vote 2 down vote accepted

No, it is not compatible at all. If your motherboard doesn't support registered memory then you can't use it.

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Thanks for the clear and prompt answer! :) – Giordano Mar 26 '12 at 10:11

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