I’m not sure quite where the cause of this problems lies, but I’m experiencing problems with USB flash drives on my hackintosh. I’ve had a Kingston 4Gb stick for a while now that works fine under Windows and has worked fine on Leopard. The last time the device was used with the hackintosh was around three months ago so it’s not clear when the problem started. Every time I try to copy files to the drive the transfer speed is worse than USB 1 spec, and the estimated time to completion when moving 200Mb earlier today was over an hour.
The reason for using the drive again was that two 8Gb flash sticks arrived today and I was thinking of doing some comparisons with Leopard running from Hard Drive and Flash Memory. The Kingston drive went in for some speed tests which turned out to be pointless since both old and new flash memory was appallingly slow. Trying to speed test the new flash drives (Dane-Elec brand) even froze Leopard a couple of times.
A search of several sites turned up many users suffering the same problem under Leopard, and these people are running genuine Apple hardware. I’ve had intermittent problems in the past with things like password prompting when waking from sleep, and it’s difficult to discern if the problem is because I’m running unsupported hardware or a Leopard issue. With many people reporting transfer speed problems after upgrading from 10.4 Tiger to 10.5 Leopard I’m leaning toward Leopard being the problem, so more searching is needed.
UPDATE I tried the same flash drives on my Macbook and got similar results, transfers were no higher than USB 1 speeds. Next test was a Panasonic Lumix camera connected by USB cable, speeds were also USB 1. The surprise was a Kingston 1Gb SD card in an Integral SDHC USB card reader which was transfering at the speeds I would expect, looked around 7Mb/s. Finder reported 900Mb would take less than a minute to copy.
A 60Gb 2.5inch SATA drive in a USB case was also tested and worked very fast, with finder copying 185Mb to the drive in just a few seconds and showing that 2.58Gb would be copied from the drive in under a minute. Looks like the problem is confined to USB flash drives.