I wouldn’t be recommending any sort of upgrade since it’s likely to be worse than what comes in the TR.
Most USB (very rare) and PCMCIA video cards are 2D affairs that offer very minor improvements for older notebooks and just multimonitor support. It can’t actually make your graphics better on the notebook’s screen. The even worse problem with either one of these solutions is that the bus (USB 2.0 or PCMCIA-to-PCI) is way too bandwidth limited to offer any sort of performance increase.
USB 2.0 offers only 60MB/s (max theoretical) of bandwidth while PCMCIA Type II/III offers 133MB/s over the PCI bus. Of course, it has to share that 133MB/s with every other PCI device. So, you’re lucky to see even 1/3 of that.
The built-in Intel Extreme Graphics 2 has AGP 8x which offers a theoretical 2GB/s of bandwidth. It’s also built-into the main chipset so you can’t upgrade it with another chip.
Even if you could get something faster than the Intel Extreme Graphics 2 that worked over USB2 or PCMCIA, it would be pointless since there’s not enough bandwidth available to keep up with the graphics chip.
