Moved to Mobile section.
Assuming you're talking about replacing or upgrading the processor in a Laptop/Notebook computer (the part number you posted is that of a mobile Athlon XP-M), i recommend you contact your Laptop's manufacturer and ask them about any possible upgrades and more importantly whether they have released any updated BIOS-versions to support newer processors.
Generally, replacing your current CPU with a part of the same OPN (Ordering part number, i.e. 'AXMH1800FQQ3C'

will be no problem.
Theoretically, any (mobile) Socket A processor with an OPN that starts with 'AXM
H...', i.e. 45W Mainstream parts, should work with your machine although it can't be guaranteed if there is no BIOS-support.
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The opinions expressed above do not represent those of Advanced Micro Devices or any of their affiliates.
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