BIOS Issues and CD Boot on Packard Bell

Hello,

I have a Packard Bell E6315 computer. With this, I have 3 interchangeable 2.5" hard drives, which means I do a lot of formatting and reinstalling of Windows and Linux. My problem is that I cannot boot from my CDs when starting the computer.

At first, it shows a welcome screen telling me that if I press F2, I can enter the BIOS setup, or if I press F8, I enter the BOOT menu (Floppy disk, CD, Hard disk, or network).

For a month, both options F2 and F8 worked perfectly, and I could also boot from my CDs, but suddenly, I can no longer enter the BIOS setup (I press F2 30 times, nothing happens, so it defaults to F8), and when I select (boot from cd-rom), it boots from the hard drive (while if I select the floppy drive, it tells me there is none, which is normal since I don't have a drive, but it still recognizes it). And when I select PXE-LAN (network), it searches for a machine that can send me data.

So I would like to know if there is a solution; I've had this computer since December 2003, I believe. I've tried disassembling it, removing the RAM sticks, taking out the fan, disconnecting the BIOS battery, removing the processor and putting everything back together, and rebooting, but nothing changes!

I even have 2 DVD drives for laptops, and the problem is the same, regardless of the drive, while both recognize the CDs well under Windows.

I also specify that it's not the CDs' fault because I have previously managed to install from these CDs without problems.

I hope there is a solution because it's becoming very annoying.
Thank you.

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