You need to set your page file (aka swap file) to use the ram disk. Also the temp folders as well.
Right click on my computer, goto properties.
Click on the Advanced tab
At the bottom click on "environment variable"
and where you see the temp and tmp directories, set them to point to your ram drive. Note: you will either put them in the root folder of the ram drive or a subfolder, but if you use a subfolder, you will need to make those directories on every boot via batch file. Probably a lot easier to use the root of the ram drive.
Click on okay and get back to the advanced tab again and click on Performance -> Settings button and then Advance tab at the top. then "change" under "Virtual Memory" at the bottom. You will see all your drives there. Click on each one and select "no paging file" and then "set". Except for the ram drive. Click on the ram drive and select "system managed" or you can do custom, but i just let Windows do it. Not a huge difference. When done, click on set again. So now above under drives you should see all physical hard drives set to none and your ram drive set to whatever you set it at if you used "custom" or blank if you set windows manage it.
Okay everything out and reboot.
BE SURE EVERYTHING IS WORKING BEFORE YOU DO THIS. Your ram drive has to work and be loaded first thing. Otherwise windows will be trying to set the pagefile and temp files on an non-existent drive.
If you don't see a huge performance difference either you didn't do something right or you lack the observational sensitivities to detect a change in time. ;-)
For this to work well you must have at least 8gig of memory in the machine. 4gig and under will be used by windows and apps, 4 gig above used by the ram drive.
To be sure your ram drive is using the memory ABOVE the 4 gig limit you need to use the /PAE swtich. If you don't then you will be stealing RAM from down below which takes away from Windows and only makes it use the swap file more... which is a downward spiral in overhead. To make sure you using the ram over the 4gig limit, consult the ramdrive software. You will most likely need to use the /PAE switch. Just search google for "boot.ini /PAE", it's easy to find.
PSS. Once you have it all working well you can go into every other app you and set their temp folder to the ram drive as well. Most use the windows environment variables, but I have some that do not and you'll need to manually configure those.
PSSS. Depending on how much RAM you have that you can dedicate to the ramdrive you can do lots of really cool advanced stuff like preloading some commonly used software to run off the ram drive however that is pretty advanced as you have to make sure Windows knows where the app and all it's folders are. An easy way to do this is to uninstall the app first then reinstall it but this time install it to the ram drive. NOTE how much space the app uses and make sure you have more than enough space on the ram drive taking into account your swap file, temp files, etc. If you had 32gig of Ramdrive you can do quit a bit. It is easy to get yourself in trouble if you do this, so take your time and make backups. Installing apps to a ram drive risk loss of data and corruption so be sure you are familiar with this part before you attempt it. Also you will need to copy the entire app folder from the ram drive to the hard drive before you close down. And then recopy it back to the ram drive every time you boot. IT'S A LOT OF WORK, but it could be worth it depending on your apps. Some of the ramdrive software will do this for you.