Re: Ubuntu dual boot installation on HP pavilion dv7.
Two important points ...
First, if Ubuntu fails to run after a Wubi install, it is unlikely that it will then run after installing in its own partition. Wubi is only an INSTALLATION METHOD, not a different version of Ubuntu. What you end up running is the same thing -- whether or not it is its own partition.
Also, the hardware is the same, regardless of the installation method. IF Ubuntu can't see your video device after a Wubi installation, that will be the same problem after a different installation.
Best approach is to boot from a LiveCD and find out what is needed to get Ubuntu to run on your PC without problems. Any changes you make for that are going to have to be repeated when you do the install.
Second, do NOT use the Ubuntu installer to shrink down your Win7 setup using the Slider. That can corrupt the Win7 OS and render it unbootable.
If you really want to press ahead with dual-booting with Win7, then read the details below ...
You need to see the disk partitions when you boot into Win7 and use the Disk Management utility. Count the partitions you see. IF there are already four of them, that is the maximum allowed. IF you FORCE the creation of another, not only will that automatically convert the Basic Volumes into Dynamic Disks (something you do NOT want to do), it will then PREVENT the installation of Linux.
If you decide to continue on with dual-boot, then use ONLY the Win7 Disk Management utility to shrink the Win7 OS partition to make room on the drive. Win7 is very finicky about its OS partition being messed with from "outside" with other tools -- like GParted. While it may be OK, it's more likely to result in filesystem corruption, which will then render Win7 unbootable.
And, after you create some free space, do NOT format it using the Win7 Disk Management utility; leave it as free space.
Then BEFORE you install Ubuntu, use the Win7 Backup feature to create and burn a Win7 Repair CD. You might need this later if the dual-boot install corrupts the Win7 boot loader.
When you then install Ubuntu, use the "Something Else" option to allow Manual Partitioning.
Ubuntu 15.04 Mate, Mint 17.1; MS Win 8.1, Win10 TP.
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