This is for 2 reasons, I just want the parition mixed with the same drive instead of the method I use now of deleting partition, creating new one, keeping the 100mb one and deleting the leftover then merging them. In other words I just want it to create 1 partition with the whole drive with the 100mb mixed with the rest of the drive without doing it manually. I guess I want to do the same for Windows 8.1 too.
Or: At disk select screen during installation, open command prompt with Shift+F10. Type "diskpart". Then "select disk 0" (Replace 0 with the disk you're installing on, if you're not sure, use the "list disk" command). Then type "create partition primary". Then "format recommended quick label="Whateveryouwant" (label is actually surrounded by quotes in diskpart). Then type "active" and hit enter. Close the command prompt, hit refresh, and install on the newly created partition.
You can do it with an unattend file or a diskpart script. I've got an extensive diskpart/apply script in my sig, but it requires WAIK5+ As far as an unattend file, there are positives and negatives to using one. Yes you can have it automatically format a drive, but it doesn't let you specify the drive before you do it. You have to specify in the xml. Also it loves to automatically set a lot of other settings for you when you use an unattend file; such as windows updates.
Seems to have more cons then pros then, but the 2nd method may be the best because I have noticed mostly on laptops it puts the partition on the 1st drive even if you want to install windows to the 2nd drive, so if I did that would it also stop the annoyance of it overwriting a linux bootloader on another drive?
[This only applies to my testing with MRB drives only, not GPT] Here's what I've been doing at installation: 1 - Delete all partitions on the destination drive. 2 - Create a new partition. When prompted on how much space to allocate, use it all. This way, no 100-350MB OEM partition is created. After you have your first OS up and running, use Disk Administrator or AOMEI/EASUS partition tools to create more partitions as needed. As far as I can tell, the OEM partition wants (or needs to be) at the very start of the physical disk. If that space isn't available, it never gets created no matter how many more OS's are installed. Currently have a 256GB SSD with four primary partitions (the maximum) with W8.1 Pro, W7 Ultimate, Vista Ultimate and XP Professional. (It ain't perfect - EasyBCD 2.2 doesn't work with W8.1, I have to boot from W8.1 media and do a "repair" to get W8.1 to boot. Pretty sure it's "unsigned driver" related. But don't no one help me. Not the purpose of this thread and I'm still delusional enough to believe I can fix it on my own).