RV535 [Radeon X1650 PRO] no more 3d after upgrade

[Luca Ferrari]

Hi all,
after an automatic upgrade to 14.10 I've lost my 3d effects, and all
seems in place.
My card is a radeon x1650 pro, here's what lshw shows:

% lshw -c video

  *-display:0
       description: VGA compatible controller
       product: RV535 [Radeon X1650 PRO]
       vendor: Advanced Micro Devices, Inc. [AMD/ATI]
       physical id: 0
       bus info: pci at 0000:02:00.0
       version: 9e
       width: 64 bits
       clock: 33MHz
       capabilities: vga_controller bus_master cap_list rom
       configuration: driver=radeon latency=0
...

and modules loaded:

% lsmod | grep radeon
radeon               1420877  3
i2c_algo_bit           13406  1 radeon
ttm                    97680  1 radeon
drm_kms_helper         61627  1 radeon
drm                   310919  6 ttm,drm_kms_helper,radeon

I've no xorg.conf file, and radeontop is showing no GPU activity at
all (video mem is lower than 45%). Before doing a do-release-upgrade
everything was working fine, so what am I missing?

Thanks,
Luca