noapic and USB2 high-speed

[Jesus Jr M Salvo]

I am still running FC6 on a Compaq Presario V6107AU notebook with an
AMD Turionx64 x2, although I am still using an x86 kernel:

$ uname -mprv
2.6.20-1.2948.fc6 #1 SMP Fri Apr 27 19:48:40 EDT 2007 i686 athlon

When I initially tried to install FC6 on this notebook, the only I was
able to boot was by adding the noapic kernel parameter. During all
that time, I always have this error on dmesg:

irq 7: nobody cared (try booting with the "irqpoll" option)
 [<c044f74a>] __report_bad_irq+0x36/0x7d
 [<c044f92b>] note_interrupt+0x19a/0x1d7
 [<c044eec1>] handle_IRQ_event+0x1a/0x3f
 [<c0450230>] handle_level_irq+0xa7/0xdf
 [<c0450189>] handle_level_irq+0x0/0xdf
 [<c0406268>] do_IRQ+0xb5/0xdd
 [<c04048f3>] common_interrupt+0x23/0x28
 [<c0402d52>] default_idle+0x0/0x3e
 [<c0402d7e>] default_idle+0x2c/0x3e
 [<c04023d0>] cpu_idle+0x9e/0xb7
 [<c074b812>] start_kernel+0x3b6/0x3be
 [<c074b25a>] unknown_bootoption+0x0/0x202
 =======================
handlers:
[<c05877a3>] (usb_hcd_irq+0x0/0x4e)
Disabling IRQ #7

I also have a built-in nVidia graphics controller and an nVidia
chipset. I am also now using nVidia's proprietary graphics driver.

However, I realised later that the only way I could get high-speed
working with  my USB 2.0 devices was if I _remove_ the "noapic" kernel
parameter. That is, if I have noapic, I only get up to full-speed (
12Mbps ). Without noapic, I get high-speed ( 480Mbps ). What's more, I
occassionally get lock-ups with X if I do not have noapic.

To summarise my problems:

1) If I have noapic, I am not able to achieve high-speed with my USB
2.0 devices, but I do not seem to get any lock-ups with X.

2) If I do not have noapic, I am able to achieve high-speed with my
USB 2.0 devices, but I occassionally get lock-ups with X ... say once
or twice a day ... most often during screen savers. I am using "The
Matrix" screen saver, but _not_ the opengl version.

What is also interesting was that, in the intial kernel that came with
the FC6 CD,  the only way I was able to boot was with the noapic
parameter. So through all the kernel upgrades, I always have noapic
... until about last month when I tried to get high-speed USB working
and tried _not_ having noapic. So I was surprised that with later
kernels, I was able to actually boot without having noapic.

Any ideas ? Suggestions ?
How can I have high-speed USB 2.0 working _and_ not having to deal
with  lock-ups with X?

Regards,

John