Under certain circumstances, the Deep Sleep setting on your OptiPlex 380/390 may lead to No-POST or No-Power events. In order to prevent any of these situations from happening, it’s imperative that you take one of the following actions:
1. Manually change the Deep Sleep Control setting to “Disabled” on the Power Management section of the BIOS setup utility
2. Perform a BIOS update – There is a new version of the OptiPlex 390 BIOS (A05) available on support.dell.com for download and install
By making any of these changes you are not going to impact the performance of your system or exceed any Environmental standards. If you choose not to follow any of the above actions, your standard warranty will still cover your system in case of failure (where applicable).
We appreciate your understanding and patience as we work diligently to avoid this situation from happening in the future.
Please feel free to contact your account manager to assist you if you have any questions.
Thanks,
Mourin@Dell