ckonstantinos

My Vaio SVS-15 is "HP SC" i.e. position A

Hello Andre and Jaclaz, I can confirm that the problem for the high CPU usage was the pin on the SATA connector that notifies if the tray is closed or open. I searched today online for a caddy with a switch on the SATA connector and found this that ships to Sydney: http://www.aliexpress.com/item/New-Internal-optical-drives-Slot-in-IDE-Combo-DW-224SL-BD-ROM/611259789.html And then I realised that since last night I read about the solution I haven't checked if mine has the switch So I uninstalled it and guess what, yes it has I changed the position of the switch and now my vaio idle is back to 0% and the battery life has doubled again! I also realised that most of the suppliers don't even know about this feature of the caddies they are selling, so anyone that has a high CPU and has installed a caddy PLEASE CHECK YOUR CADDY FOR A SWITCH!! This is an image of the switch: https://dl.dropboxusercontent.com/u/105145405/caddy%20switch.jpg

Hi Jaclaz, Thank you very much for your answer and your investigation. I guess the easiest solution is to find one of those caddies with a switch. Cheers Konstantinos

I guess this is the answer for my problem. I just found it online: "Normally the optical drive sends a signal to BIOS to let it know that the optical drive is closed and the computer is allowed to read the optical medium. If this signal stays “open” then the BIOS keeps sending this signal. Because the HDD Caddy does not eject the tray, it causes unnecessary CPU usage during idle because the signal cannot be closed. To prevent this problem, the SATA or PATA converter board needs to be modified." I guess there is no software or setting workaround this problem, only hardware modification

Hi again, Actually I discovered that even if there is no device physically installed in the optical drive slot the problem still exists! This tells me that the problem is not the second hard drive but the absence of the optical drive. So I think that the driver for the optical drive is looking for it causing high interrupts or something like this. So I reinstalled the optical drive and from the device manager I selected "disable" and then "uninstall" for the optical drive hoping that it will stop looking for it. Then I shut down the computer and reinstalled the second hard drive but the high CPU usage is still there! I think the optical drive driver is not uninstalled properly or something like this. Any suggestions please? Thank you. Konstantinos

Hi MagicAndre, Thank you for your reply. Finally I have found the source of the problem but I don't know how to fix it! Some time ago I replaced my broken optical drive with a second hard drive. I installed it using a HD caddy adapter. So now I reinstalled my broken optical drive and the high CPU usage disappeared! Now few strange things are happening: When I have the second HD installed (via caddy) It works but in the BIOS under "second hard drive" it says "none". So I guess it is because it is connected in the optical drive slot. Also in the device manager the second HD appears as hard drive and "working properly" and both hard drives use the generic Microsoft (2006) driver and are recognised as SCSI devices. Under disk management the second HD is listed as "Healthy, Active, Primary". The strange thing is that even if I disable the second HD from the device manager or from the BIOS by disabling the optical drive the high CPU usage problem still persists. Only if I remove is and install the optical drive the CPU goes back to normal! I tried to update the HD driver from the automatic update of the device manager but it couldn't find a newer driver. Do you have any suggestions to solve the problem and being able to use my second internal hard drive? Thank you very much! Konstantinos

Hi MagicAndre, Thank you for your guide! I have the same problem with the process "System" keeping the CPU constantly at 10-20%. Actually I have a vaio with "stamina-speed" switch. When I select "stamina" the CPU is constantly at 10%. When I select "speed" the CPU is at 20%. I followed your instructions and I think the responsible threads are ACPI and HAL. I tried to find a new BIOS but it seems that I have the latest one. I installed all the windows updates but nothing changed (I have windows 8.1). I changed my power saving setting but nothing improved. Please can you have a look at my DPC_Interrupt.etl because I don't know what else to do and this problem is eating my battery! Here is my DPC_Interrupt.etl: https://dl.dropboxusercontent.com/u/105145405/DPC_Interrupt.zip Thank you so much Konstantinos