Acer Aspire 5517. Windows 7 Home Premium x64 (preinstalled). Latest updates/drivers installed. When the laptop is idle, CPU usage hovers around 48% (over 90% of one of the two processor cores). The Resource Monitor shows System Interrupts using almost all of the CPU time. If applications are run, they can use the remaining available CPU time, but System Interrupts continues to use about 46%. The problem disappears when I reboot, but returns when the laptop wakes up after going to sleep. A workaround is to disable the LAN adapter (which is not in use). CPU usage immediately reduces to normal and stays there (at least so far). A Google search shows the problem to be widespread and longstanding, although the immediate culprit isn't always the LAN adapter (sometimes it's the card reader, USB controller, HD sound, etc.).

Hi,This issue is widely spread indeed, anything is possible. As the issue appears after resuming from sleep, and the issue can workarounded by disabling LAN adapter,it can be more related to the LAN adapter as this device can not resume after the sleep. If so, here we can change the settings to bypass the issue:open device manager-> right click on your LAN adapter->switch to Power Management tab->make surethe checkbox of Allow the computer to turn off this device to save power is unchecked. Since the LAN adapter is not in use, you can simply disable it permanantly. In case it is used in the future, you can install the driver for Win7 to avoid issues.Meanwhile, based on the similar cases recently, it is strongly recommended to update the chipset driver.If none of the situation is true, you can continue device clean boot which disables other potentially unstable hardware such as the sound, modem, network card, and CD-R drive and so on totroubleshoot the issue.

Thanks for the suggestions. I wonder why Windows 7 isn't automatically supplying the appropriate drivers.

Hi, Microsoft do not write drivers for third party devices, especially the OEM version (Original Equipment Manufacturer). To achieve their user friendly goals, they will have certain basic drivers builded in, but most of build-in drivers can not use the device to their best.Better to install the latestaccording tothe third party makers. In addition, certain device driver will bereleased from Windows update channel for user's convenience. To do this, Run Device Manager, right click on the LAN adapters and choose "Update driver software" It is also not suggested as a whole. (The Windows Update site lists driver updates only based on hardware ID scan results despite various environments.)

Hi,I had the same problem with an Acer Aspire 5532 on Win7 x64. But instead of disabling the Ethernet adapter, I rolled back the driver to version 1.0.0.10 (7/27/2009) and that fixed it. The problematic driver seems to be 1.0.0.15 dated 10/21/2009.

Microsoft do not write drivers for third party devices, especially the OEM version (Original Equipment Manufacturer). Sure, but I often see third-party drivers offered as optional updates by Windows Update. For example, on my desktop PC, Windows Update has provided the latest drivers from Dell (monitor), Logitech (webcam), Hauppauge (TV card), Realtek (LAN), and nVidia (video). So I'm curious why the same doesn't happen with Aspire laptop PCs (especially when the default drivers apparently do not work properly).

I believe most of the drivers were still released from third party offical webside instead of Windows updates. Besides,the majoritydrivers from Wu websites are for pinters and graphics cards.