I am trying to upgrade Windows 8 to 8.1 on my old (650i?) computer and am getting this error:
unable to create ramdisk - 0xc1900101-0x20017
 
The error seems to be common with people with old nVidia motherboards, see this discussion:
http://answers.microsoft.com/en-us/windows/forum/windows8_1-windows_install/windows-81-install-unable-to-create-ramdisk/887b5adc-86ce-4c37-9c58-72eca5f712d4
 
Does anybody have a work around? I believe these motherboards are not officially supported for Windows 8.
 

Dear tvalentijin,
 
If you should continue to have a problem after trying rjohnson11's recommendations then I do apologize as we have looked further into this for you and I can confirm that Windows 8.1 is not officially supported on this motherboard.

Well I'm still here to try and help you if you wish.

Windows 8.1 does run OK on the old NFORCE boards.
Updating from 8 to 8.1 is a problem as the error you are seeing is affecting many people.
Not just those with NFORCE
 
You can do an upgrade, read the thread I linked to below
As long as you don't mind doing a PC refresh.
http://forums.steampowered.com/forums/showthread.php?t=3192157&page=2
read posts 28 and 29
 
Personally I have 8.1 on a USB key and do clean installs.
 

I found this on a another forum and it worked for me.
 
 
Here's the contents of it pasted verbatim.....
..........
Fixed!
 
TL;DR version:
 
Ran the following command in an administrative command line window:
 
bcdedit /deletevalue {badmemory} badmemorylist
 
Once done, I started the 10240 upgrade via Windows Update and it installed successfully.
 
Theory
 
The error 0xc0000017 says there isn't enough memory available to create a ramdisk device, which didn't seem possible, having 4GB of RAM.
 
While researching the Windows Recovery Environment, I came upon tools like bcdedit which lets you see and modify boot configuration data.  When I ran "bcdedit /enum all" in an administrative command line, i noticed a number of entries in a section called "badmemory".  There were probably 50-60 of them.
 
I read about what the badmemory entries are and why there were in the bcd from this site:
 

 
Windows doesn't use the RAM blocks marked as "badmemory" in the BCD in an effort to prevent memory errors down the road.
 
So, my theory was that the error for 0xc0000017 was slightly misleading... that perhaps what it's really saying is:
 
There isn't enough contiguous memory available to create a ramdisk device.
 
The thought is that my memory is "fragmented" because there are bad blocks scattered throughout, so there isn't one solid, contiguous block large enough to fit the recovery environment disk image into memory.
 
With that in mind, I used the command at the top of this post to clear the badmemory list so Windows would start using them again.  I figured, since the memory blocks are being marked bad as a precautionary measure (Windows predictively assuming they'll go bad), clearing the list would free them up for use and, if Windows wants to mark them bad again later, that's fine, as long as I get through the 10240 upgrade.
 
Turns out that worked.  Clearing the badmemory list in the bcd freed up enough contiguous RAM space for the disk image to load via ramdisk and allowed the upgrade to complete successfully.
 
Update
 
Found this.  The section at the bottom,"Memory Requirements" confirms that WinRE requires a large enough portion of contiguous memory in order to work.  What it doesn't mention is that the BCD's "badmemory" list also contributes to a lack of contiguous memory space:
 

 

Good info but this thread is almost two years old when you posted.