I had the same problem, and this thread solved it.
OS: TC 3.0
CPU: Intel Atom 230
Chipset: Intel 945G
Just trying to install graphics-2.6.33.3-tinycore with the Appbrowser would black-screen my computer, but after a boot with the "nomodeset" option the installation succeeded.
With graphics-2.6.33.3-tinycore installed, confless invocation of Xorg-7.5 fails with a black screen, whereas confless invocation of Xorg-7.4 works fine.
I'm delighted to find the solution to my problem immediately, by searching these forums.
Thanks Curaga!