Best solution for increasing range

Hello all,

Hope someone can help. I'm using two 54g PCI cards to connect two PCs in ad
hoc mode. I use a software router on the PC connected to the net and share
the connection with the other. All worked smoothly until I had to move one
of the PCs (further away). Now throughput speeds have dropped dramatically
and the network occasionally drops out altogether.

My cards are Belkin. I notice that they sell a replacement antenna that is
designed to sit on the desktop and extend range. Do you think this will
work?

Thanks.