Correction:
When I load fglrx, it says: (modprobe fglrx) [fglrx] Maximum main memory to use for locked dma buffers: 430 MBytes. ACPI: PCI Interrupt Link [APC4] enabled at IRQ 19ACPI: PCI Interrupt 0000:02:00.0[A] -> Link [APC4] -> GSI 19 (level, high) -> IRQ 201[fglrx] module loaded - fglrx 8.14.13 [Jun 8 2005] on minor 0
Then, when I start the X server: (startx) I get this in /var/log/kern.log:
[fglrx:firegl_unlock] *ERROR* Process 3559 using kernel context 0
ps -A | grep 3559 3559 ? 00:00:05 X