Personally I would upgrade for SD work, you'd need to get advice from someone else on HD but here goes...

Nvidia 128mb Geforce4 mx 440 with AGP 8x ---> PCI-E graphics card running at 16 speed and if you want to connect up a second monitor it is very useful

Celeron 2.0 ghz CPU---> Get a Intel Pentium 4 with Hyperthreading at least with 3.2Ghz cpu

1.0gb DDR RAM ---> should be fine but may need more for HD work

80gb HD ---> way tooooo small, get the largest you can afford and keep the small one for the operating system and all your other files

DVD burner and firewire port.

Make sure the Front Side Bus on the motherboard is clocked at 800mhz -- you need speed

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