Something just doesn't add up with Company of heroes. AlexZ posted on the socket 754 topic an in-game screenshot with only 444mb of VRAM utilized. So I took a GTS 250 last night and installed into the system. The one and only difference between 9800GTX+ and GTS 250 is the amount of onboard memory: 512mb, respectively 1024mb.

I started a 6 players game and, as you can see in the screenshots, it takes 739mb out of 1024mb of the GTS 250 and 2.2gb of system ram. Also as the game progresses and the AI players put up an increasing number of units, the framerate drops more and more, indicating a CPU bottleneck similar to how Age of empires 2 plays on a Pentium 3 for example when it slows down to a crawl after reaching high number of units.
Also, at the suggestion of AlexZ - to whom I thank - I took Sysinternals Process Explorer and monitored CPU usage during the game. Both cores where loaded at around 70% indicating the game uses 2 cores. Need a second monitor for real time monitoring.

GeForce GTS 250 seems to be a good choice for the tests as opposed to 9800GTX+ which will suffer from VRAM shortage. I only saw 700 MB VRAM being used in Company of Heroes temporarily. For some reason it then drops to below 500MB, sometimes I see about 600MB. Probably also map size dependent.

RAM usage displayed is probably overall RAM usage, since you have additional background apps that's the reason you see 2.2GB used.

Exactly! MSI afterburner is eating around 400mb of RAM only for itself! 2gb would probably be enough on small maps like that one above if one will disable everything! And I mean everything: msi afterbuner, fraps, Everest/Aida and so on. But than you have Fear, Quake 4 and others who eat RAM for breakfast and you would still hit the page file with just 2gb installed.
After testing a few games my conclusion regarding RAM is clear: for late era Windows XP games - 2005&2006 - 4gb is required and not an extravaganza.

So I replaced the Eizo S2100 with 2 monitors from storage: Samsung 940bf that i bought myself back in 2006 after I enter the workforce and got the first money - and of course the first thing on the shopping list was a brand new system with 2 monitors! 19 inch with 1280*1024 resolution at 75hz. 5:4 - not perfect but good enough for retro gaming.