Of course it's always a possibility that your cables are faulty. But the more common cause for low transfer speed is having your ethernet settings misconfigured.
On your PC, go to the device manager and check the properties of your network adapter. Under the advanced tab there will be a link speed/duplex mode setting. Keep in mind:
- Full duplex is only advantageous when you're transfering files in both directions at the same time.
- Full duplex is not possible with a hub, only with a crossover cable or a switch. If you force it anyway you will suffer slow performance. Better to stick with half in that case.
- If you have more than 2 ethernet devices, buy a switch instead of a hub. Switches don't cost much more than hubs these days and they are far more reliable and flexible.
- If you do have a hub make sure all devices run at the same setting (either 10 Mbps or 100 Mbps half duplex. Automatic doesn't always work well with hubs so try the fixed setting first). 10/100 dual speed hubs use a simple store and forward buffer mechanism between the low and high speed segments, this buffer is small causing packets to be dropped and retransmissions -> speed loss. So use only 10 OR 100.
- If you're using a crossover cable, make sure the devices on either end are configured identically (either 10 or 100, full or half. 100 full is ideal.)
- If you have a managed switch make sure your port settings are exactly the same as the devices attached to it. Set the port to automatic and the ethernet card as well. Or set both to 100 full. Do not combine an automatic with a fixed setting.
I get over 5000 KB/s either way. Not as fast as FTP between two fast PCs with a lot of memory and fast hard drives, but quite usable.