I had the same issue for the past 6 months and finally fixed it. The main issue is the BIOS image of the Inspiron 5675 Desktop is corrupted and it needs to be flashed again. Disconnect the power cable from the Inspiron 5675 Desktop ON A SECONDARY PC: 1. Download the latest Inspiron 5675 Desktop BIOS .RCV format from here2. Click Other Formats to see the .RCV file3. Rename the file and save it as BIOS_IMG.rcv4. Copy the file to a USB thumb drive formatted as FAT325.Insert the USB thumb drive into the CORRUPTED BIOS PC and plug in the power cable to the Inspiron 5675 Desktop6. Press and hold ctrl and esc key and click your power button and keep pressing ctrl and esc and wait a couple seconds until the Inspiron 5675 Desktop will boot7. A BIOS Recovery menu will show up. Follow the procedure to recover the BIOS Hope it works for you:)  
Hello, I have problem with inspiron 5675 - after pressing power button it starts and all lights turns on and all fans starts to spin but nothing more happens. After 30-40 seconds power button starts to blink 3 times amber, short pause, 6 times white, long pause and it repeats. Tried to google what this pattern means, but can't find anything. I really would appreciate if someone can help me with this. 
Inspiron 5675, problem, blinking 3 amber, 6 white