I would have to agree with him. At the most, a higher clocked 7600 GT (80 nm) would be top. There is no point in spending more right now on graphics, because it will be bottlenecked by the CPU. While some others might perform better, like dos1986 said, it'd be better to just save that money for a new board and all.
Well I already ordered a card, which is almost the same, except its somewhat cheaper, and the Core and Memory speeds is reduced a bit. Your saying the card won't even work, or just that it isn't worth the money cause the CPU prevents it from doing its full potential?
The GDDR3 has nothing to do with the system ram. You'll be fine. CPU limited in some cases, but other games you will see a benefit over a 7600GT or X1650XT.
(Not that this matters now)
Depending what you paid for it, it may have been a wise move. Priced under $125 it's great as the step down cards are rare and still over $100 AR. Why pay that much for a slower/older card. Priced around $150 and up, you would have been better off IMO with something else. I like the HIS IceQ's alot and have owned quite a few of them. But they aren't worth it sometimes if priced way higher. The Sapphire 512MB or His non iceQ AGP HD2600XT are a better deal for $110 than I have seen the IceQ go for. http://www.newegg.com/Product/Product.aspx?Item=N82E168... http://www.newegg.com/Product/Product.aspx?Item=N82E168...
edit: my big beef right now with the AGP 2600XT, is the price has stayed the same, while the PCI-e versions have dropped. You can get a Sapphire PCI-e for $50 AR now. Or a GDDR4 MSI with the Witcher for $62AR.