Your MoBo with the Intel 810 chipset should handle up to PIII850MHz (100MHz FSB only) and up to 512MB of PC66 or PC100 SDRAM.
These were the specs of Intel 810 chipset.
Also, to be more sure, you can download the standard version of
SiSoft Sandra 2004 and use it to detect your MoBo. (it might fail to detect it though)
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