USB 2.0 and P2B-DS

[Jordell Jarnell]

Current printer is worn out. New Canon i960 wants USB 2.0. Looking at
Belkin F5U220rw USB 2.0 pci card. Have the following questions in
priority order.

1) ANY issues with ANY USB 2.0 pci card in a P2B-DS (1.06,D03)?
2) Does a PCI bus as old as the P2B-DS handle the USB 2.0 speed or
does it essentially "throttle" it to 1.1 speed?
3)ANYone with experience with the Belkin card and/or recommendations.
Thank you for any help provided.

 

[Nikolaos Tampakis]

Current printer is worn out. New Canon i960 wants USB 2.0. Looking at
Belkin F5U220rw USB 2.0 pci card. Have the following questions in
priority order.

1) ANY issues with ANY USB 2.0 pci card in a P2B-DS (1.06,D03)?

As long as the card doesn't break any PCI laws I can't see any problems
arising.

2) Does a PCI bus as old as the P2B-DS handle the USB 2.0 speed or
does it essentially "throttle" it to 1.1 speed?

Yes it handles it perfectly well. You may not get the same performance
as with a chipset-based USB 2.0 implementation, but on the whole 480
Mbps is about 57 MB/sec *theoretical* bandwidth (and whether it's
utilised in its whole by most USB 2.0 high-speed devices is doubtful).
Your "old" PCI bus 133 MB/sec theoretical bandwidth so no problems
there. My PCI bus is the same as yours (and possibly of somewhat worse
performance considering I'm on a VIA chipset) but my USB 2.0 card fits
happily.

3)ANYone with experience with the Belkin card and/or recommendations.
Thank you for any help provided.

I'm slightly partial to USB 2.0 cards based on the NEC chips. Not
because I despise others, but because this chip seems to work well indeed.
I use Adaptec's DuoConnect card (initial revision) on a dual PIII-S
system, so I can verify proper functionality in an SMP configuration. I
get slightly crippled speeds when using fast USB 2.0 devices (e.g. an
external hard disk) compared to the chipset-based i845 USB 2.0
controller in my laptop but otherwise it's ok and no stability concerns
whatsoever. The card of course has a NEC controller for its USB 2.0 part.
I don't know the specific Belkin card but a) belkin is reputable and b)
the card (based on the photo on their site at least) does indeed use the
NEC chip so it seems to be a safe bet.
There are, by the way, two revisions of the NEC controller, B0 and B1. I
don't know of any functional differences though. Both have passed
hi-speed certification so I don't think it should be a major concern.
These controllers are natively supported by windows XP SP1's (and
probably Win2k SP4's) USB 2.0 drivers, too.

Regards
Nikos

 

[Stephan Grossklass]

Current printer is worn out. New Canon i960 wants USB 2.0.

Nah, it'll most probably run fine with USB 1.1. I've got an i865 on a
P2B-D here (1.06 D03), and that worked right out of the box. (OK, I got
the latest drivers first, the supplied ones were a bit dated.)

1) ANY issues with ANY USB 2.0 pci card in a P2B-DS (1.06,D03)?

A number of USB2 cards will not run when the PCI bus does not provide
3.3V (as it's the case for the P2B-D(S) with its PCI 2.1
implementation). If it works, fine, if it doesn't, try another. (I'd
recommend NEC based cards.)

Stephan

 

[P2B]

Nah, it'll most probably run fine with USB 1.1. I've got an i865 on a
P2B-D here (1.06 D03), and that worked right out of the box. (OK, I got
the latest drivers first, the supplied ones were a bit dated.)




A number of USB2 cards will not run when the PCI bus does not provide
3.3V (as it's the case for the P2B-D(S)

Interesting. In that case why does the 3.3v LED on my POST diagnostic
card light up when it's plugged into a P2B-DS PCI slot?

Just the other day I fixed a P2B-DS with no power to the memory - the
3.3v LED was off initially, but came on as usual after I replaced a FET
in the 3.3v regulator circuitry.

P2B

 

[Stephan Grossklass]

Interesting. In that case why does the 3.3v LED on my POST diagnostic
card light up when it's plugged into a P2B-DS PCI slot?

Well, it could be that Asus added PCI 2.2 support later, like Gigabyte
apparently did on the GA-6BXD. (Incidentally, what's the big difference
between 2.1 and 2.2 anyway? I always thought it's mostly 3.3V standby
power.) You do not happen to have one of those stubborn USB2 cards that
refuse to work in, say, an older P2B?

Just the other day I fixed a P2B-DS with no power to the memory - the
3.3v LED was off initially, but came on as usual after I replaced a FET
in the 3.3v regulator circuitry.

Hmm. This would imply that the +3.3V supplied to the PCI bus comes from
the VIO voltage regulator. That should be okay with the default 3.20 V
I/O, but 3.5 V (as to be found on all the other Asus BX boards) would
already be out of the +/- 5% tolerance.

Stephan

 

[Nikolaos Tampakis]

Nah, it'll most probably run fine with USB 1.1. I've got an i865 on a
P2B-D here (1.06 D03), and that worked right out of the box. (OK, I got
the latest drivers first, the supplied ones were a bit dated.)




A number of USB2 cards will not run when the PCI bus does not provide
3.3V (as it's the case for the P2B-D(S) with its PCI 2.1
implementation). If it works, fine, if it doesn't, try another. (I'd
recommend NEC based cards.)

Stephan

I will not bet on it, but I think that if a PCI card is 3.3 volt *only*,
then it ought to not have the second notch, the one away from the metal
plate that is, but only the one closer to it.
As long as it has both notches, then it should be a dual voltage (3.3 or
5 volts) capable card.
Exceptions should probably be considered bad manufacturing examples.

Regards
Nikos

 

[P2B]

Well, it could be that Asus added PCI 2.2 support later, like Gigabyte
apparently did on the GA-6BXD. (Incidentally, what's the big difference
between 2.1 and 2.2 anyway? I always thought it's mostly 3.3V standby
power.) You do not happen to have one of those stubborn USB2 cards that
refuse to work in, say, an older P2B?

That's possible, but I don't think it's the answer - I've worked on a
lot of P2Bs and never seen the 3.3v LED off unless there was a VIO
problem, including (recently) a P2B-DS 1.04 and a P2B 1.02.

I don't know much about PCI specifications, and to date I've gotten by
with the onboard USB ports - so no USB2 cards here, stubborn or
otherwise

Hmm. This would imply that the +3.3V supplied to the PCI bus comes from
the VIO voltage regulator. That should be okay with the default 3.20 V
I/O, but 3.5 V (as to be found on all the other Asus BX boards) would
already be out of the +/- 5% tolerance.

Bit hard to tell, but it appears to be VIO at the PCI slot. I just poked
around on the P2B-DS 1.06 I have running on the bench (with modified
VIO), and measured 3.48v at the ATX power connector, and 3.38v at both
the DIMM and PCI slots. BIOS shows 3.4v.

I suppose to really understand you'd have to download PCI specs and
probe the board more extensively. It might explain why Asus set VIO
lower on the dual P2Bs, which has always been something of a mystery to me.

P2B