A common problem during Linux installation (or afterwards) on laptops are missing lines at the bottom of the text console display, so the last command lines or the login prompt are not shown on the screen. Depending on the problem it might help:
Either using FrameBuffer, e.g. using a Kernel with framebuffer support and a boot option like vga=791, for details see the FrameBuffer-HOWTO.
Or disabling FrameBuffer, e.g. using a boot option like vga=normal or another resolution Also, you could try passing video=vga16:off on the installer boot prompt.
As a workaround often it is possible to switch to a second console e.g. <ALT>+<F2> , because this effect is often only related to the first console.
Check if there are VGA and video boot options configured in the bootloader (e.g. grub, lilo). Try to disable them at least partly, look for options like ywrap, etc.
Check the BIOS for display settings, often (older) Toshiba laptops behave like this.
Issue the command resize to get the correct screen size into the system.
If none of the above helps, you may try to run a start-up-script, which has to run at the end of the boot process. The script has to contain the clear command and/or the reset.