Sorry, didn't explain what happens with KMS.
Using the default Xorg (ie. no xorg.conf), we get:
(EE) open /dev/fb0: No such device <- expected as KMS and framebuffer clash, so no vga= parameter for the kernel
(EE) intel(0): No kernel modesetting driver detected
(EE) Screens(s) found, but none have a usable configuration
Fatal server error:
no screens found
Now, doing an Xorg -configure, editing the conf to use the vesa driver, and using the correct modeline, I can get 1920x1080. However, the vesa driver won't rotate (ie. either using xrandr or the rotate option in xorg.conf). Now I have tried:
i915.modeset=1, and
i915.modeset=0
on the kernel line (from grub)
and added /etc/modprobe.d/915.conf, with:
options i915 modeset=1, and
options i915 modeset=0
(ie. tried both, but not at the same time obviously).
I booted a live version of mint, and grabbed the modeline, so I know it is correct. When using 915resolution (and vesa), you can't specify the sync polarity (ie. hsync and vsync), so although the card will go into 1920x1080, it won't display on the monitor. The vesa server (Xvesa) will happily rotate a lower res, eg. Xvesa -screen 1280x1024x24@270, but won't work with 1920x1080 because of the incorrect sync polarities (checked the DPMS reported modes in mint).
I tried to get 7.4 working (non KMS) but haven't (yet) got the non KMS drivers. I might just have to go back to a 2.x version. The reason I used microcore is that I have a 32M card on which the OS and app/data has to sit
Cheers...