Bump....
I posted about this in the other thread. I was getting horrible speeds uploading from PC to Xbox (around 400kbps). I've tried WS_FTP and FlashFXP with same results. I've tried setting my NIC settings to every combination possible (half/full duplex, 10/100 speed, and auto-detect). After replacing the original Seagate drive with a Western Digital WD1200BB (7200RPM 120gig) drive, I'm getting upload speeds of 3MB/sec (24mbps). It's better than before but it's still no where near saturating the network.
FYI, my PC is running Windows XP and my NIC card is a D-Link DFE-530TX PCI Fast Ethernet Adapter (10/100 auto-sensing). The PC and the xbox are both hooked up to a Linksys BEFW11S4 wireless access point/router/4-port switch with standard CAT-5e cables (Note that communication between the PC and xbox is NOT going over the wireless so that is not the problem). I'm running the latest version of EvoX 1.8.3285 (i think). It's whatever one comes with the Slayer's Auto-Install ISO that was just released.
I've tried to narrow down the problem by running disk drive benchmarks on my PC to make sure my computer is reading from the hard drive fast enough. Sure enough, it's reading at around 24MB/sec from the C: drive (40gig Maxtor ATA/133). I'll probably do a packet dump of a transfer and see if I can find anything "wierd" there.