While I am not sure about the Video Card, I am guessing not, I ran Tiger and later Leopard on a 2.4 GHz P4 with 512, later 786MBs and on an 80GB Hard Drive. It ran with out any problems with Tiger, but Leopard (10.5.1 and 10.5.2) had a kernel panic here and there.
I would say it should work, best thing to do is to try it out.

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MSI P43 Neo3-F
EVGA 250GTS 1GB
2GBs RAM
750GB SATA HDD - OS 10.6.4 (Software Update)
500GB SATA RAID HDD - Windows 7 64bit
DVD - R/W PATA