Title says it all, Skyrim only lets you use 2GB for some reason, so I wanted to use more.

If you do too, firstly download Explorer Suite or CFF Explorer from here http://www.ntcore.com/exsuite.php

The rest I got from a link which I had to view through google cache for some reason, so I'm just going to quote the guy (a Robin Scott?)

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Click the folder icon or go to File -> Open and browse your PC for TESV.exe.

Click on File Header at the left, find Characteristics at the right, and click the Click here blue button.

Tick App can handle >2GB address space.

Click OK. Save by clicking the disk icon or going to 'File -> Save.

Overwrite the file when it asks you to.

NOTE: If you use this method, you need to keep the backup of the exe file you changed with CFF Explorer.
When you update your game, you will need to copy the backup exe back to folder and replace the edited exe file.

Go to the folder which has the executable file you changed.
Delete the current *.exe file.
Rename the backup executable back to the original name, now you can safely update/upgrade.
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Enjoy! I can now run Skyrim on Ultra instead of just High with 100% fluency (Ultra would be perfect in one scenario, then totally glitch and crash on me in others, with no explanation I could figure out).

Disclaimer: I did not come up with this fix, if you don't backup your .exe and it breaks, I'm sorry not my fault, just telling you what I did and why, and I hope it works if you need it

it uses only 2GB what? RAM?

gigastar:
I think im missing something here.

If the game runs perfectly fine with 2GB RAM, why would you want it to use more?

Make it run better on higher settings.
Speaking of which, I may have to get this mod thingy. I just got a new total of 4GB and I'm getting occasional framerate dips. Thanks, OP!

Fun fact: this works on pretty much any 32 bit .exe. One of the first things you're supposed to do when setting up one of the various graphical mod packages of Morrowind is to run a program that does basically what the OP described. I can't imagine running Morrowind 2011 on 2 gigs of RAM. With that package running on the highest settings, my computer (which isn't much by modern standards, but may as well be a supercomputer by 2002 standards) gets about 5 FPS, and that's after running the RAM fix.

Aah... that explains why it's been running a bit choppier than I'd have expected, even after I lowered it to High graphics. Thanks!

Hey I'm glad this was useful to some people, I learnt too that I can do this for many other games, which has me interested (like Counter Strike Condition Zero, Empire Total War, Deus Ex Human Revolution, The Witcher 2, just to name a few icons I can see on my desktop, oh! and Dirt 3).

Conza:
Hey I'm glad this was useful to some people, I learnt too that I can do this for many other games, which has me interested (like Counter Strike Condition Zero, Empire Total War, Deus Ex Human Revolution, The Witcher 2, just to name a few icons I can see on my desktop, oh! and Dirt 3).

Can you explain how the update thing works? WE need a copy of the original TESV.exe that we need to put into the Skyrim folder when we want to update? And then do this all over again after the update is done?

Soviet Heavy:

Conza:
Hey I'm glad this was useful to some people, I learnt too that I can do this for many other games, which has me interested (like Counter Strike Condition Zero, Empire Total War, Deus Ex Human Revolution, The Witcher 2, just to name a few icons I can see on my desktop, oh! and Dirt 3).

Can you explain how the update thing works? WE need a copy of the original TESV.exe that we need to put into the Skyrim folder when we want to update? And then do this all over again after the update is done?

Yes, so you back up your .exe, then with the original you alter it as the instructions say.

Then, when it comes time for an update, you rename the backup to the original, update it, then back it up and repeat the process.

But how many updates will there be? and its quite a quick process anyway, especially for the benefits (imo).

gigastar:
I think im missing something here.

If the game runs perfectly fine with 2GB RAM, why would you want it to use more?

It doesn't always. Memory-cluttering can actually make this a problem in long playing sessions (and let's be real, Skyrim is a huge game you could play for days without pause and still not complete it).

Soviet Heavy:
Yes, so you back up your .exe, then with the original you alter it as the instructions say.

Then, when it comes time for an update, you rename the backup to the original, update it, then back it up and repeat the process.

But how many updates will there be? and its quite a quick process anyway, especially for the benefits (imo).

Conza:
Yes, so you back up your .exe, then with the original you alter it as the instructions say.

Then, when it comes time for an update, you rename the backup to the original, update it, then back it up and repeat the process.

But how many updates will there be? and its quite a quick process anyway, especially for the benefits (imo).

This software is a much simpler solution. It can enable and disable the fix on the fly. No need for all the tedious backing up with your solution:
http://www.techpowerup.com/forums/showthread.php?t=112556

I had a real stability problem until I enabled the usage of all of my RAM. Now I haven't had a single CTD since.

Athinira:

Soviet Heavy:
Yes, so you back up your .exe, then with the original you alter it as the instructions say.

Then, when it comes time for an update, you rename the backup to the original, update it, then back it up and repeat the process.

But how many updates will there be? and its quite a quick process anyway, especially for the benefits (imo).

Conza:
Yes, so you back up your .exe, then with the original you alter it as the instructions say.

Then, when it comes time for an update, you rename the backup to the original, update it, then back it up and repeat the process.

But how many updates will there be? and its quite a quick process anyway, especially for the benefits (imo).

This software is a much simpler solution. It can enable and disable the fix on the fly. No need for all the tedious backing up with your solution:
http://www.techpowerup.com/forums/showthread.php?t=112556

Yeah, I looked at it, my one is much simplier, but thanks for contributing.