# of USB ports

  • Thread starter Thread starter JohnO
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JohnO

Easy question....how many USB ports are on some of the newer motherboards?
Six on the back....plus more on headers?

What about SATA ports, have they gone much beyond four?

-John O
 
JohnO said:
Easy question....how many USB ports are on some of the newer motherboards?
Six on the back....plus more on headers?

What about SATA ports, have they gone much beyond four?

-John O
Click to expand...

You can use the "advanced search" on the Newegg motherboard page to
get this information.

Intel motherboards:

For SATA, 4+4 or 6+2 might be max (Southbridge plus a separate
controller). Intel Southbridges have six SATA. For USB, I see one
with 8 ports on the back.

AMD motherboards:

For AMD motherboards, 6 USB on the back looks like the limit.
And perhaps 6 SATA.

HTH,
Paul
 
Easy question....how many USB ports are on some of the newer motherboards?
Six on the back....plus more on headers?

What about SATA ports, have they gone much beyond four?

-John O
Click to expand...
This question has NOTHING to do with XP and is out of place HERE.

Ask elsewhere
 
OldDuke said:
This question has NOTHING to do with XP and is out of place HERE.

Ask elsewhere
Click to expand...

How many USB ports does Win XP/Vista support? Not devices (127) but ports.
And, can I add 127 devices to each port within Win XP?

-John O
 
JohnO said:
How many USB ports does Win XP/Vista support? Not devices (127) but ports.
And, can I add 127 devices to each port within Win XP?

-John O
Click to expand...
You need 127*X ports?
My god man, what are you running? A factory?
 
Big Al said:
You need 127*X ports?
My god man, what are you running? A factory?
Click to expand...

LOL, no. It's just a point of interest. It all gets back to the 'hub' and
'root hub' stuff that I can't wrap my brain around.

-John O
 
OldDuke said:
This question has NOTHING to do with XP and is out of place HERE.

Ask elsewhere
Click to expand...

OldDuke is our resident mentally retarded ****wit.

Ignore him - everyone else does.
 
JohnO said:
How many USB ports does Win XP/Vista support? Not devices (127) but ports.
And, can I add 127 devices to each port within Win XP?
Click to expand...
I assume your question is theoretical.

USB supports up to 127 peripheral devices which can be connected with USB
hubs to expand the number of connectors. The hubs can be connected more or
less in any configuration that you please, but the hub tree must be
dendritic* and there can be no more than 15 hubs between the host and any
peripheral.

*The A and B connector configuration forces this topology.
 
How many USB ports does Win XP/Vista support? Not devices (127) but
I assume your question is theoretical.

USB supports up to 127 peripheral devices which can be connected with USB
hubs to expand the number of connectors. The hubs can be connected more
or less in any configuration that you please, but the hub tree must be
dendritic* and there can be no more than 15 hubs between the host and any
peripheral.

*The A and B connector configuration forces this topology.
Click to expand...

Thanks, I found some collaborating info at usbmadesimple.co.uk.

Can I do the 127-thing on *each* of my two physical laptop USB ports, and
each of the six ports on the rear of my desktop mobo? Or, is there just one
root hub in there being split into several physical ports by an internal
hub...using up one of my allowed hubs in the dendritic chain? This kind of
thing is hard to google.

And yes, the question is academic, but only partially. I'm writing a
tutorial and hands-on lab, the end-user will connect a few devices and we'll
use Microsoft's UVCView USB utility to examine the ports and devices and the
power they're claiming. The theory says "127", but the practical application
is fuzzy and I don't see anyone explaining it.

(reminds me of the commonly quoted file name size limit: 254/255...everyone
quoted the MS-provided number, but nobody bothered to try it. I did, and the
results were different than what MS implied. Today most of us know that
"C:\" and takes away three of that 254...)

-John O
 
JohnO said:
Thanks, I found some collaborating info at usbmadesimple.co.uk.

Can I do the 127-thing on *each* of my two physical laptop USB ports, and
each of the six ports on the rear of my desktop mobo? Or, is there just
one root hub in there being split into several physical ports by an
internal hub...using up one of my allowed hubs in the dendritic chain?
This kind of thing is hard to google.

And yes, the question is academic, but only partially. I'm writing a
tutorial and hands-on lab, the end-user will connect a few devices and
we'll use Microsoft's UVCView USB utility to examine the ports and devices
and the power they're claiming. The theory says "127", but the practical
application is fuzzy and I don't see anyone explaining it.

(reminds me of the commonly quoted file name size limit:
254/255...everyone quoted the MS-provided number, but nobody bothered to
try it. I did, and the results were different than what MS implied. Today
most of us know that "C:\" and takes away three of that 254...)

-John O
Click to expand...

<answering my own question...>

Per wiki: "USB host may have multiple host controllers and each host
controller may provide one or more USB ports. Up to 127 devices, including
the hub devices, may be connected to a single host controller."

So, my Intel mobo could handle 889 devices.

<wondering how to get the purchase order approved to test this>

-John O
 
JohnO said:
<answering my own question...>

Per wiki: "USB host may have multiple host controllers and each host
controller may provide one or more USB ports. Up to 127 devices, including
the hub devices, may be connected to a single host controller."

So, my Intel mobo could handle 889 devices.

<wondering how to get the purchase order approved to test this>

-John O
Click to expand...

I think you will be having "severe propagation and timing issues" a long
time before you get to 127 devices. Much less stacking the wiring and
hubs to accomodate nearly 900 USB items. ;-)
 
Bob I said:
I think you will be having "severe propagation and timing issues" a long
time before you get to 127 devices. Much less stacking the wiring and hubs
to accomodate nearly 900 USB items. ;-)
Click to expand...

You're not helping the cause, Bob, even though you're certainly right. :-)
I remember reading about someone building a 127-device system back when USB
was new, it was mostly keyboards and mice and hubs, and a stunt at a Comdex
or something.

-John O
 
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