Problem booting ubuntu on i7 laptop

[Petranidis]

Hello,

I am experiencing a strange situation with my new core i7 4 GB DDR3 laptop.
The manufacturer had allready windows 7 installed in it and I installed
karmic ubuntu 9.4 with the nolapic option on. With out nolapic the machine
crashed. After that I upgraded the distibution to 9.10 and the machine worked
just fine. After the first reboot it booted until the splash screen shown and just before
the login screen it crashed. I change the boot options where now appears the message:
"crashkernel=384M-2G-64M,2G-128M" and add the nolapic option and the machine boots just
fine but it only detects and uses one of the four CPU cores. After updating the kernel to the
latest version the machine booted fine without the nolapic option and detected all the cores.
Although,after the first reboot with this configuration it returned to it's previous behavior.Now if
I do not disable the lapic it crashes. Has anyone experienced anything similar?Should I clean the kernel or any file before shuting down the machine?

[prudhivisekhar]

Try installing ubuntu again with default settings. The kernel should automaticallu detect the 4 cores.

[Petranidis]

Thanks for your reply. I tried it but it just wont work. After showing the progress bar I only get a black screen.