I have just replaced my 320 GB HDD-drive 5400 rpm with a 240 SSD from ADATA in my leptop.
Now the multiresolution segmentation algorithm in eCognition Developper is working better, is much more faster and the maximum image size to process has increased from 4000x4000 pixels to 7000x7000 pixels (I am using the same CPU and RAM configuration).
So, now i see that SSD's are more efficient thant classic HDD's.