The only difference is the IC7-G has gigabit lan and 4 SATA connectors, while the IC7 has 10/100 ethernet and 2 SATA connectors. Other than that, they are IDENTICAL. So, to answer your question, either one depending on your usage requirements.
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Rig #2: (folding 24/7)
2.8E @ 3.22, IS7, BFG 6800 Ultra, 2X512 Geil PC4000, 60GB Maxtor, Aspire 500 watt.
Rig #3: (folding 24/7 @ 75%)
2.6B @2.9, IC7, 9800XT, 2X256 Corsair PC3200, 120GB WD, Aspire 500 watt.
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