Replaced the videocard today since the old one died.
Also took the oppertunity to install a new 4TB disk and remove a defective 2TB disk.
The data on the 2TB disk was succesfully recovered with dd_rescue to an image file on the new 4TB disk with a LVM2 setup.
hopefully today going to be able to copy the data from the rescue image onto a full partition in the LVM2 setup, after that going to take some time to add another 4TB disk and setup some mirroring.