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When I try to install Debian Linux (newest stable as of 6.2.2013, x64) on a Dell OptiPlex 740 I keep getting this error message right after I choose "Install" from the main menu (the hdd is empty):

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(254,32)

I have tried using a liveCD and that won't boot up either, screen just goes almost white with a white cursor blinking in the top left corner.

Windows 7 Ult x64 installs fine on the same computer. I have installed Debian on several computers (servers) before this and never had any problems. What's wrong?

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What happens on the lines above this error message? It will usually give you some more info about the partitions it's found and what-have-you. Also, what type of drives are you using? – Xyon Feb 6 '13 at 13:04
Isn't the optiplex an UEFI one? There where a lot of issues in the last weeks with samsung (+others) uefi laptops and Linux (up to no longer working samsung notebooks) – Offler Feb 6 '13 at 13:08
Have you checked the md5sum of the iso you downloaded? – terdon Feb 6 '13 at 13:21
@Xyon: There is just this one line. The drive is your common SATA2 hdd. – Akke Feb 6 '13 at 13:27
@Offler: How can I check this? – Akke Feb 6 '13 at 13:27

Two things to check:

  • Try booting from USB, not CD, as sometimes CD drives cannot be detected on startup
  • In the BIOS, set the SATA controller mode to AHCI, potentially IDE, but never RAID, and also "AHCI (Linux)" often does not work with Linux.
share|improve this answer
Thanks, I'll try :) – Akke Feb 7 '13 at 12:21
I've done the SATA controller configuration on many (10+) other motherboards, but can't seem to find it on this one. I made a USB netinst drive and it still gives me the same error msg. What do? – Akke Feb 7 '13 at 13:06
Check the manual, on page 8 it talks about AHCI settings. – Stefan Seidel Feb 7 '13 at 13:22

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