[bobwhite1]

I recently had a new mother board installed and since this time my cpu will no sleep. The monitor will. I have Vista home OS.

[leroys1000]

Enter the BIOS setup as the computer starts to boot.
Make sure sleep mode in the bios is set to S3 or higher.
Probably under power options.
S1 and S2 sleep modes,the fans will keep running.
S3 or higher and the fans will shut down.

[bobwhite1]

I did as you directed leroys but had to change back to S1. After I went to S3 my fan kept going up and down in speed after going to sleep mode and I could not bring the monitor back up until I turned of the computer using the power button and then rebooting. The CPU still didn't go to sleep mode and was not working right in S3. I went back into BIOS setup and went back to S1 and everything is back to normal. Except, I still can't get sleep mode for the CPU. Any other suggestions? TIA Bob

[leroys1000]

Can be hard to troubleshoot standby problems without
actually sitting at the computer.
It sounds like you may be having problems with an incompatable
peice of hardware interfering with the stanby function.
You might check power options and advanced power options
in control panel to see if everything is set properly.
You need at least S3 to shut the fans down.
What happens if you use hibernate instead of standby?

[bobwhite1]

leroys, first of all everythings working fine, the cpu goes to sleep as well as the monitor. For the purpose of others possibily learning from my problems let me go through what I encountered in fixing this problem. The first problem was that because I replaced the motherboard the F12 key did not open the bios screen. I had to go from F1 through F12 with no success. I then remember reading somewhere that the delete key might work so as a last resort I tried that and had success, the bios screen came up. The first time I changed from S1 to S3 and re-booted everything went haywire as I indicated in my second post. The fan got noisy and started fluxuating up and down like it was trying to turn off but couldn't. I had to turn the cpu off at the power switch and came back in the bios mode. Set the unit back to S1, saved and the cpu re-booted itself. Everything was back to normal but still had the problem. I set everyback to default and then went to msconfig and hid all the microsoft program and disabled all the other programs, then tried to put the unit to sleep but that didn't work so I assume it wasn't a program preventing the unit from going into the sleep mode. I went back into msconfig and put everything back to normal. I then decided to try one more time and went back into the bios and set it up with S3, clicked on F10 to save, the computer re-booted on its own and now works fine with a few changes I assume because of the new motherboard. Now when the unit goes to sleep from timing out or manually the Power on switch doesn't turn orange but flashes green. I also cannot bring it out of the sleep mode by moving the mouse or clicking on keys, I have to press the Power switch lightly one time and the unit comes out of sleep. I can live with that. Thanks alot for all your help and patience. Bob

[leroys1000]

Check the advanced power options in control panel.
Make sure that USB selective suspend is enabled.
For the keyboard and mouse,you will need to check the properties
for them in device manager.
In the properties for each,there should be a selection that says allow
this device to wake the computer.
Also check the bios for wake options.
You don't want anything enabled in there that will just wake the computer
by itself,like WOL(wake on LAN)timers or anything like that.
Just enable anything that has to do with wake on keyboard or mouse.

[bobwhite1]

I did everything you said and all is back to normal to include the power switch which was set for flashing and I put it back to color in the bio, also enabled the mouse and keyboard in the bios. Once again thanks for everything. Bob