It needs to be DDR.
SDRAM is different, with different numbers of pins, etc.
Assuming a typo or brain freeze. <grin>

For a look at the specs, see here?:
<http://www.crucial.com/store/listparts.aspx?model=Dimension%202400%20Series&pl=Dell&cat=RAM>
It you expand all the FAQ there for this model
it says  total max 2G with max 1G per slot,
no dual channel and no ECC.

                                                Rick Glazier

--------------------------------------------------
From: "Dave Greenwood"
> Hi I wonder if you can help?
> I have a Dell Dimension 2400 and have tried to install a 1GB SDRAM PC2700 DIMM but the system will not boot. My friend also has a
> Dimension 2400 which is running a 1GB DIMM plus a 256MB DIMM with no problem. Why?
  

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