My Transcend SD USB reader works fine and so does my LaCie FW powered drive, both FW400 and 800.
But both my FW Compact Flash readers (Sandisk and Lexar) as well as several OWC Ext SATA drives either freeze my system or don't mount- I try hot swapping, and have tried starting up with the drives attached. What's up? ALL the readers and drives work on my MBP in OS 10.4
The HNTosh runs 10.5.8

Try this, backup AppleHPET.kext, and delete it from your extensions reboot and try to plug in your Card reader

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HP Pavilion Elite m9250f
iAtkos v5i (10.5.8), Asus IPIBL-LB MOD BIOS, Intel Quad Core Q6600, 4GB RAM (800mhz), 2x500GB, nVidia 8600GT (Works), ALC888S (Works), Wireless RT73 (Works), LAN (Works) - How to Install - Blog - Hardware Combos - FAQ by TJ2K7
Macbook Pro 13"
Follow meh: @icchansan

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