USB hub - high CPU use?

blackmyst · Post by **blackmyst** » Mon Aug 14, 2006 8:16 pm

Are USB hubs supposed to take up like 20-30% of the CPU? It seems the more stuff I connect to it, the higher it goes. And yes, I've tried to just connect all the devices directly to the PC and it was all normal, so I know it's the hub and not something else.

Deathlike2 · Post by **Deathlike2** » Mon Aug 14, 2006 8:23 pm

IIRC, USB doesn't use any form of hardware acceleration.. so you it has to use your CPU.. I believe Firewire doesn't suffer from this though.

funkyass · Post by **funkyass** » Mon Aug 14, 2006 9:31 pm

how USB root hubs do you have

take a peek in the device manager, it'll tell you how many you have. Try to spread the number of devices evenly across the root hubs.

But if you don't need a particular device, unplug it. If something happens on a root hub, the CPU has to ask each device on that hub if it did something.

blackmyst · Post by **blackmyst** » Mon Aug 14, 2006 11:53 pm

Well my win2k is Dutch, so I'm not exactly sure what they translate "root hub" to...

However, I'm not sure if this is what you mean, but I've got one external USB hub that I connect all my devices to, which would be my modem, my keyboard and my tablet (which is also my mouse), and I've got a few other things that I don't use very often and which I only plug in when I do.

I can only connect them to this external hub because I've got my PC in a different room from where I'm working.

Does this really need to take that much CPU? I've got an athlon XP 2400+, if this was a pentium 2 or something I'd expect something like this, but...

kevman · Post by **kevman** » Tue Aug 15, 2006 1:49 am

No, certainly not.

I have a 4 port hub and use all 4 ports nearly all the time.

My computer idles at 0%.

Maybe your hub is shit.

sweener2001 · Post by **sweener2001** » Tue Aug 15, 2006 2:01 am

i second that vote.

blackmyst · Post by **blackmyst** » Tue Aug 15, 2006 2:02 am

Maybe it is. I got this one.

I guess I'll email them about it. Last time I ever let the store sell me something of a brand I've never heard of, without doing research....

Edit: now that I think of it, maybe this is somehow related: at startup, the bios does not start checking ram or drives until I unplug the hub. After it's done I can plug it back in. Weird.

Deathlike2 · Post by **Deathlike2** » Tue Aug 15, 2006 3:06 am

That seems like a BIOS issue.. but it could be the USB hub that sucks.

SquareHead · Post by **SquareHead** » Tue Aug 15, 2006 6:58 am

blackmyst wrote:Edit: now that I think of it, maybe this is somehow related: at startup, the bios does not start checking ram or drives until I unplug the hub. After it's done I can plug it back in. Weird.

I have a similar issue with one of my external harddrives.
My BIOS freezes through scaning my USB ports unless I have it powered off during boottime.

blackmyst · Post by **blackmyst** » Wed Aug 16, 2006 9:18 pm

kevman wrote:No, certainly not.

I have a 4 port hub and use all 4 ports nearly all the time.

My computer idles at 0%.

Maybe your hub is shit.

Does the stuff you use include a keyboard, mouse, and modem?

If this is supposed to be normal for a USB hub that has all those things attached then fuck it, I'll just buy a whole bunch of USB extention cables and use those. I can hardly use my computer, what bullshit is this.

If it's not supposed to be normal, could you tell me the brand of yours?

funkyass · Post by **funkyass** » Wed Aug 16, 2006 11:30 pm

A USB modem you say? Problem located.

blackmyst · Post by **blackmyst** » Thu Aug 17, 2006 12:06 am

Actually, I've found that it's pretty much only my tablet/mouse and my super smartjoy that do it - and only when connected to the hub.

blackmyst · Post by **blackmyst** » Fri Sep 29, 2006 12:04 am

So I made a fresh windows installation the other day, and the problem seems to have vanished. The CPU sits pretty much unused no matter what I connect to the hub. Hmm. Well, thought I'd mention it in case it might be useful to someone.

kevman · Post by **kevman** » Fri Sep 29, 2006 1:18 am

Huh, well, maybe a driver issue, then. I recall my mobo not having USB2.0 in win2k without drivers.

And yes, my mouse goes through the hub.

PHoNyMiKe · Post by **PHoNyMiKe** » Fri Sep 29, 2006 2:01 am

maybe you had a virus in ur hub!

blackmyst · Post by **blackmyst** » Sat Sep 30, 2006 7:30 am

Hah. I thought I'd install my PC's USB drivers since I hadn't yet after formatting my HD, even though the USB was working properly. And guess what? Thing's gobbling up the CPU again. I uninstall the driver, problem gone again. So fuck the drivers then, it seems to work fine without them.

Or would there be any negative side effects?

SquareHead · Post by **SquareHead** » Sat Sep 30, 2006 7:52 am

blackmyst wrote:Hah. I thought I'd install my PC's USB drivers since I hadn't yet after formatting my HD, even though the USB was working properly. And guess what? Thing's gobbling up the CPU again. I uninstall the driver, problem gone again. So fuck the drivers then, it seems to work fine without them.

Or would there be any negative side effects?

IIRC most times its better off to use Windows' USB drivers that what came with the motherboard/add-in card.

kevman · Post by **kevman** » Sat Sep 30, 2006 8:13 pm

Check to make sure that your USB systems are USB2.0. Chances are, with Win2k, they are actually operating at 1.0 speeds. Easiest way is to use HDspeed
with a USB flashdrive that's 2.0. If your speed is greater than 2 meg, you are good.