When mapping, be sure to keep your nose between your eyes and your mouth.

riiiiiiiiiiiiiiight...

It is advised by me to have at least 1 gigabyte of RAM when mapping. 512 mb will soon make Hammer act weird, especially if your map grows bigger and your undo's are becoming more and bigger. Though it is possible to map with only 512 mb of RAM, it will be difficult and irritating. That is my finding with Hammer.

Even 1 gigabyte is slightly low, as Hammer will still act weird after some time. The lowest ammount I have found to work under any condition (for Portal) is 1.5 gigabyte.

With "weird" I mean constantly getting warning messages, and if you click on anything in the 3D-view, Hammer will start moving all your brushes around. That's a sign of low RAM, at least for me.

Please note that this only counts for Portal. I have no idea about Half-Life 2 and CS:S, since I have never mapped for them, and Team Fortress 2 acts weird after a while even with 1.5 gigabyte.

The best would be 2 gigabytes, probably. But certainly not less than 1 gigabyte. Of course I know that most mappers and gamers have powerhouse-pc's nowadays, but probably new and upcoming mappers don't, so it is usefull for them to know this. It has nothing to do with mapping itself, but more with Hammer's functionality.

User has been banned for this post. --msleeper

I would add:
Fix your leaks. You can see you have a leak in the compile console that vbsp is screaming ugly messages at you. If you have some light entities in map and the lighting looks ugly after compiling with lights, you have a leak.
Just tested it on myself, so don't do the same mistake

Okay now I am locking this thread because it turned into exactly what I didn't want.

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