I would be very interested in if this actually has a positive effect on battery life..... I never use the camera anyway, so no great loss to me.

Without the patch, the issue affects all USB controllers on the eeePC that have (or had) a device connected to it. In regards to the web cam controller, Microsoft may not be aware that the USB Video Class drivers or a driver tied to that class may also need to be patched, guess we should send them an email.

I had a few hours to spare after the Xmas feast , so I decided to make a simple .NET 2.0 tray app that interfaces with Microsoft's DevCon command-line Device Manager application in order to toggle the webcam's USB controller off/on.

You can download the eeePC Webcam Tray App at http://dastudio.net/eeePC/eeePCCamTray.zip

Extract the 'eeePCCamTray' directory to your drive, double click on 'eeePCCamTray.exe' to launch the application. You should see a miniature version of the application icon in XP's notification tray.

The tray app is straightforward to use:

- Hovering your mouse over the icon in the tray displays a tooltip that lets you know whether or not your eeePC webcam is currently enabled or disabled.

- Right clicking on the icon will present you with either an Enable Webcam, or Disable Webcam option, and also a "Close" option.

You should create a shortcut to the application in "Start-> All Programs-> Startup", doing so will allow the application to be loaded up once Windows has started.

If the application does not load you likely need to download .NET 2.0 framework http://www.microsoft.com/downloads/deta … laylang=en

If it still doesn't work (hopefully we all have the same webcam hardware)... well too bad

Last edited by NoeeePC4MeWellMaybe... (2008-01-05 8:53:10 am)

awesome i'll try this if i have some time later today

Taskmanager's algorithm for computing memory consumption does not work correctly with .Net apps. I'll let Tim Anderson explain why this is the case since his article does a pretty good job at doing so  

http://www.itwriting.com/dotnetmem.php

Since using the tray app to disable the web cam, I definitely see an improvement in my fanless idle temperature. The temperature decreases when the webcam controller is disabled, while it slowly increases when enabled. I’m pretty positive that our battery life will be slightly improved (maybe +10/15 minutes).

Just another update:

WiFi on battery power uptime is 1hr 31 minutes as reported by the Atheros Utility, and XP's battery memter has just switched to 60% remaining. My screen brightness has been at 50%, and I have my WiFi adaptor's Transmit Power Level set at 1 mW as mentioned in http://forum.eeeuser.com/viewtopic.php?id=6408. I haven't played any mulitimedia during this usage period.

Steep, if you do not appy the XP SP2 patch, in order for the CPU to reach C3 "Deep Sleep", you'll have to disable the card reader, and the webcam, and also not plug a device into your USB ports.

Another update:

Battery meter switched to 20% remaining capacity after 2hrs 51 minutes w/WiFi On. There was a 5 minute period of heavy/constant WiFi usage when I copied a 900MB file from the network to a SDHC card. Unless the battery meter is acting up, I should get over 3 hrs w/WiFi On.

I can definitely say that my fanless eeePC feels MUCH cooler than it has ever been after being powered on for 5 hrs straight.

Final Update:

The battery completely drained, causing eeePC to shut itself off @ 3 hrs 15 minutes. As mentioned earlier, that's with Wifi on, and the screen brightness set at 50% . I may have been able to get a minute or two more if I did not transfer that large file over WiFi to the SD card  (which was only inserted for the duration of the file transfer).

Last edited by NoeeePC4MeWellMaybe... (2007-12-26 9:21:14 am)

Dear NoEEEPCwellmaybe,

Could you speak more to the reduction in fan use?  One of my few complaints about the Eee is the fan coming on and its noise.

If this patch and procedure can reduce fan use, I think it's very important and should go in the wiki with that as a caption (not to discount the other merits).

Thanks for your offering!

Thanks NoeeePC4MeWellMaybe... for the work you have done for everyone.  I love this forum.  I also agree this is sticky material. 

Jeff

8g pearl white with xp2 and loving it

Very interesting. Good work.

Do we know if this problem effects the original OS, Xandros?

Last edited by Neodudeman (2007-12-26 7:01:10 pm)

ohyes wrote:

Could you speak more to the reduction in fan use?  One of my few complaints about the Eee is the fan coming on and its noise.

I actually disabled my eee PC fan by disconnecting the fan connecter under the keyboard tray, as outlined by Daijoubu in 'The Test' topic. I was using the default Xandros OS at that point in time.

I'm unsure if it will reduce how often the CPU fan comes on after it has initially started since the BIOS turns the fan on once the CPU temp reaches 55 degrees, and does not turn it off until it drops to ~46 degrees, which for most of our eeePC's will be an impossible fan halting temperature reach.  BUT, the XP patch+tray app should increase the time it takes the fan to come on after a "cold boot".

When I posted the battery life results earlier today, my eeePC was idling around 55 degrees C after 5+hrs of light-average WiFi use. In the past, having the fanless eeePC on for 4-5 hrs straight, never moving it a cooler surface, would result in an idle temp of about 62 degrees C and the case would feel very very warm.

Neodudeman wrote:

Do we know if this problem effects the original OS, Xandros?

When I had Xandros installed I did notice that /proc/acpi/processor/CPU0/power would occasionally report that the CPU was in a C3 state, but I wouldn't know if its C3 mode switching is as aggressive as XP's.

One thing to keep in mind, is that even with the XP patch & tray app, whenever you are actively using a USB device C3 Deep Sleep state can never be obtained. So If you make a habit out of constantly playing movies from your SD card, your battery life will likely remain unchanged.

I just want to ask, What software do you guys use to record battery run time? Or is it just a sit and time with a clock type of thing?

NoeeePC4MeWellMaybe... wrote:

ohyes, you can use the webcam tray app to disable the correct USB Composite Device, since it only enables or disables a device with a hardware ID matching that of the eeePC camera.

Ah.  I hadn't read closely enough, and see now that the tray app replaces the manual disabling of the USB device.  By the way, it appears--at least on my system--to require an admin account for the tray app to be able to enable the webcam.  I am not a Windows expert, but read some time ago that one is safer to use a limited account for day to day use.  But I found that I couldn't run the tray app from my limited account.

Last edited by ohyes (2007-12-27 12:42:59 am)