E1505 new motherboard, Standby and Lock Computer don't work

Hi. I just had a new motherboard installed in my E1505 under warranty by a Dell Tech. They sent a new hard drive with it, with Windows XP already installed. I also still have my original hard drive. After the motherboard finished installing, my Standby no longer works... actually it goes into Standby, but immediately wakes up, without me touching a single thing. Also, I can't lock my computer by pushing the Windows logo + L. Using that shortcut actually logs me off the user. I tried this with both the new hard drive and the old original one. Both of these things worked fine with my old motherboard. I did a clean install of XP on the new hard drive, and still it doesn't work. So far the Dell tech that I've been talking with online and on the phone doesn't have the answer. I've been talking to him for several days now.

Anyone have any thoughts on what could cause this, or better yet, how to fix it? Thanks.

 

Have you checked your BIOS for any setting for sleep mode?

Have you checked the sleep setting in Windows XP?

 

As far as the Power Management settings, it's all normal. I don't know of any other sleep settings to adjust. But even when I try to put it in Standby by going through the Start menu, it does this. I've also tried setting the power option to 1 minute and let it sit idle, but same results. I've updated the BIOS, but I haven't checked any sleep mode. I'm not really sure what I'd be looking for

 

Something is telling me its some hardware bringing it out of sleep mode.

Like if it goes into sleep mode maybe its detecting a piece of hardware set to bring it out of it (wireless card,Ethernet card,USB etc...)

 

Is there any way to test for that or something? At least that you know of?