Laptop Power OFF when using Bootable Vista Disc

hi guys i got Toshiba Satellite P2050-57436 Laptop, vista is not booting completely any more. So i decided to reinstall vista from a bootable Disc. When I insert vista bootable disc & when i press enter key to start from DVD, then after a minute Laptop completeky power OFF, tried many times, so it never like install vista from Disc.

Can any body let me know what cause this problem, i tried with diffrent Disc like Vista, XP or Win 7, none is going to install on this Laptop.

Any help appricated.

Thanks for your answers.

thanks for your answer. i am little confuse, so can you tell me what i have to do to fix this problem.

thanks

i am still waiting for your reply, can you let me know little more clear.

thanks

any help guys, you guys having good experience, so any help appricated.

thanks

i did ram test still same problem , so i did this below

i remove hdd and connect to another pc and format completely. After this use vista disc, so shows message below.
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A required CD/DVD drive device driver is missing. If you have a driver from floppy disk, CD, DVD or USB flash drive, please insert it now.
Note : if the Windows installation media is in the CD/DVD drive, you can safely remove it for this step...Browse....Ok....Cancel (this 3 buttons shows there)after this I can't do any thing, so simply I exit the installation. And on another PC I go to manufacturar site then i look all over there is no CD/DVD driver found.
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any way i also connect external dvd drive and in bios set usb dvd 1st priority, after this never start from usb dvd. So i reput back in internal dvd drive vista disc then notice that usb drivers also required because of this resion usb dvd drive is not working & none of usb sticks are detecting there.

so is there any hope to get back on work this laptop. but still if i try win7 or win xp disc then laptop power OFF completely.

so i just stick to vista Disc, now power is ON, but driver required.

i look on manufacturar site , there is no drivers like this found like usb or dvd drivers etc.

thanks

hi there i tried all ways, i tried orignal bootable discs, win xp, vista & win 7, many diffrent discs borrow from friends. And this laptop never comes with and copy of Disc.

when win xp & win 7 disc inster laptop power OFf completely.

when vistadisc insert says like DVD driver missing, and power is ON,. with vista disc it is not turn OFF power by itself.

thanks