HI ! I received w540 last week. I run 4 vmware workstation images on the machine, and I don't want boot the system running 5 windows OS all the time, so sleep mode is a neccesity to me. However, it looks like computer does not remain is sleep mode, it wakes up after few hours, with wake source: Wake Source: Device -ACPI Lid, after this is seems to crash, and fails to start. Power led just blinks. I connect powersupply I will do cold boot up, but after log in, I can seen that battery charge is ---. Machine start charging it self, and batter after few seconds half full. Sleep mode functions again perfectly. Are there any fixes/know workarounds for this - I also been running machine from another brand, and it works more that a week under similar setup, going to sleep mode several times in day, and waking up. Lid was been open, machine is sleep mode, WLAN active, but nothign connected to machine. I am using bios 2.10, 2.11 is available, but there was no changes logged regarding sleep mode.