HDD mounted in USB enclosure vs. internal IDE

[Rubycon]

Copying about 400GB comprised of various file sizes and folders, about 1.2 million files in 54,000 folders total. Going from local disk to attached disk (USB 2.0) the process gets to about 150GB and an explorer error occurs and bombs out. The error says there is insufficient resources to copy! The computer gets dog slow too.

Taking the drive out of the enclosure and attaching it to the IDE port the DVD was on, the copy completed without issues and slowdowns.

Is there overhead with USB that takes up resources? The machine is no slouch either - QX6700 with 4GB RAM and a hardware SAS controller with 15k drives.

 

[Roguestar]

That actually sounds to me like something during the copy (caching files as they are being written) may have a tiny memory leak, something we'd not even notice except for the unfortunate who has to copy 400GB at a time? I don't imagine many people on XP copy 400GB over USB that often, perhaps there is a flaw in the memory handling or driver?