Does Oblivion need a 4GB patch if you plan on using mods? I'm noticing that my game tends to freeze, crash or locks up a lot when I'm running around the Wilderness very quickly and I am using Qarl texture pack and unique landscape compilation.

It doesn't need it to run but it does help.

I think my question isn't specific enough What I mean't to say is if you needed the 4GB patch if you plan on using texture mods.

Again, it is not needed. Does it help? Yes but it is in no way required.

This might actually be a bigger help for those crashes:

http://www.gamesas.com/topic/1486109-wip-oblivion-memory-tweaks/

The wiki article 'http://wiki.tesnexus.com/index.php/2-4GB_game_memory_limits_and_solutions' is about exactly what is involved in the 4GB patch and how it helps (or doesn't) in particular situations. It also discusses some BOOT.INI tweaks that might help get more available game RAM, depending.

The primary concerns are 32-bit or 64-bit Windows; and how much system RAM do you have? If more than 4 GB and 64-bit, most definitely. If more than 2GB and 32-bit, possibly but you still won't gain much; just maximizing what you have to about 1.8GB.

Textures replacers like Qarls put a strain on your graphics card, but the throughput from the HD to the card takes a toll on CPU, and some system RAM is always involved. The excellent Unique Landscapes also adds 'other than purely graphic' elements that also consume system RAM. In that case, you want to see if you are running out of memory (testable situation discussed in the 'http://www.gamesas.com/topic/1176244-oblivion-and-memory-usage/' thread here on the Forum).

And the link given by Supierce is an alternative to OSR, as discussed there. Worth looking over, but if you are already using and happy with OSR, probably should stick with it until all other factors are resolved before adding another (WIP) mod into the mix.

-Dubious-

Amd Phenom X4 955 Black Edition with an AMD Radeon 6870 1 GB VRAM graphics card and 8 GB of RAM so I'm guessing there is going to be a great improvement?

Decent rig, but the game will only use a single CPU core. Now it hinges upon Windows 32 or 64-bit? 32-bit normally will only recognize up to 4GB at best, but it still has to use at least 1GB for the system processes and takes 2GB by default without the BOOT.INI tweaks. But, yes it can definitely get you more memory before CTDs, and may make them less frequent. The game has memory leaks and thus eventual CTDs, but you should be able to get more (perhaps much more depending upon the LO) than an hour of play first. Not sure I would promise a "great" improvement" depending upon how you define it, but with a 64-bit OS it's more likely you can get very close to 4GB for your game memory.

Really, it's all covered in that article. Lots of variables and unexpected things tied together but previously the information was scattered in all sorts of different places. That's why I wrote it, after several lengthy discussions here. It's a technical subject with a technical solution, so it's definitely not 'an easy read', but hopefully it's educational.

-Dubious-

Very good article, thanks. I did not know, that DLLs could be patched as well.