I have yet to see a X1650 PCI graphics card, but I might be wrong. If the PCI-E series was anything to go by, then the PCI version will suck. The X16xx series from ATi has been a total disaster, it was ripped to shreds by the 7600 which is what it was supposed to be competing against.
In terms of gaming PCI cards, I don't there are any because they are not designed for gaming, the most common PCI cards would be the 9200 from ATi and the 6200 from Nvidia. But the performance is really dismal so I don't advise you to even bother. Just get a new system if you want to play games, because the current generation games will definitely require at the very least a decent AGP or PCI-E graphics card to run.