My system is not detecting DVDs but it's detecting CDs just fine.
- I have completely formatted the system but the problem still occurs
- I have a LG HL-DT-ST DVD-RAM GSA-H55N model drive.
If your problem is independent of OS (i.e. booting from DVD also does not work) and you have tried some known good DVDs you drive is likely broken.
Why is it still capable of reading CDs? Reading DVDs and CDs require different wavelengths so it could be as simple as a worn out laser for the DVD wavelength (650 nm). DVDs also have higher requirements on the optics due to smaller structure so dust or some misalignment could also be a problem.