After using a 32-bit AMD processor for years to run 32-bit applications on a Windows XP 32-bit system, I installed a new mainboard and an AMD Athlon 64 X2 (64-bit, dual-core) processor.
Immediately, I noticed the disk imaging application "Macrium Reflect" (32-bit) operated at one-tenth normal speed. But now I am puzzled-- when an Athlon 64 CPU runs a 32-bit application on a 32-bit formatted partition, should there be such a severe problem? I had read the Athlon 64 runs both 32 and 64-bit code, with the understanding 64-bit coding is simply more efficient.
Now, it seems more than a matter of relative efficiency-- I must install a 64-bit version of Windows XP (just acquired), and of most of my critical applications.
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it sounds more like a problem with the application and multicore processors, if you open task managers right click on the applications executable and select core affinity, then untick core 0 and let it work on core 1, see if the performance improves.