[LAU] hardware - Intel CPUs

[david]

On 04/16/2014 01:33 PM, Len Ovens wrote:

> On Wed, 16 Apr 2014, Jeremy Jongepier wrote:
>
>> On 04/16/2014 10:51 PM, Len Ovens wrote:
>>> It appears that the USB2 devices have problems with USB3 ports (Like the
>>> 1818vsl).
>>
>> So far I have little issues with my USB2 audio interface (not a 1818VSL)
>> and the xhci driver. I've come across that thread too and it seems the
>> issue is specific for the 1818VSL.
>
> It is specific to the Intel Ivy Bridge chipset USB3 implementation. So
> if your computer uses a different HW implementation you should be fine.
> For example a PCIe card with USB3 ports is ok or a MB that uses
> different HW. Intel admits the problem is there but will not fix it and
> feels that well written drivers will just ask the USB device for a
> resend of the missed packet !!!???  They say that nobody will notice the
> missing packet anyway??? I read this to mean "it is in the hardware now
> and there is no soft/firmware patch possible." One hopes the 4th gen
> chips are better designed. Thats what I am looking to buy. I don't have
> a USB2 device to try though.

My laptop has a 4-th gen i7 Haswell chip. My USB 1.1 audio card works 
fine on any of the USB2 or 3 ports.

My USB2 Canoscan desktop scanner, on the other hand, doesn't work on 
either variety of port on this laptop. It works just fine on the USB2 
ports on my AMD-based desktop machine (Phenom IIx4 processor and AMD 
chipset).

I found some comments saying the Canon wouldn't work on any USB3 ports, 
but I also found the closed-source commercial product VueScan which DOES 
work with the Canoscan on USB3 ports ... I suppose it's all related to 
the phases of the moon or something.

-- 
David W. Jones
gnome at hawaii.rr.com
authenticity, honesty, community
http://dancingtreefrog.com