installation problem (Kubuntu KDE4 x64)

hello to all! i am download Kubuntu 8.04 KDE4 Remix x64 and i cannot install it. After loading i see following text:
==============================================
BusyBox v.1.1.3 (Debian 1:1.1.3-5ubuntu12) Built-in shell (ash)
Enter 'help' for a list of built-in commands.
(initramfs) _
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and i cannot start installation. why this occurs? help me please

P.S. my computer have following configuration:
        Intel Core 2 Quad Q6600
        mb Gigabyte EP43-DS3L
        2 x DDR2 2048 MB 800 MHz Transcend
        PCI-E XFX 8800 GTS 512 MB DDR3
        HDD 750 GB Samsung SATA-II
        Optiarc DVD-RW AD-7200S ATA Device