Hi newjersey-brit,
Please access BIOS by pressing F2 key at Dell logo.
Navigate to 'Auto Power Time' option listed under 'Power Management' and press Enter. Check if the time is displayed as 5.30 AM.
Navigate to 'Auto Power On' and check if 'Everyday' or 'Weekdays' is selected. Use the left arrow key to highlight 'Off' and press Enter. Press 'Esc' key, select 'Save/Exit' and press Enter.
Here is the video for your reference: http://youtu.be/84xqHD-dyCk.
Hope this helps.
Please revert for any further queries.
Thanks and Regards,
Manpreet C
After nursing a Dimension3000 to an assisted suicide recently, I purchased a refurbished Optiplex 740 and it's been great for my needs, except for one puzzling anomaly; every morning at 530am, it turns on by itself. Due to my hibernate/sleep settings, it "sleeps" at 630, but I'm wondering how to fix this little problem. I've adjusted both network adapters to not wake the computer, but still it continues to happen. It never randomly powers down. Just powers up, every day. At 530am.
Any help would be greatly appreciated.

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