That will be the cause of your problem then, not enough ram. Your page file must get flogged unmercifully just running Vista let alone anything else.
Being as how Vista Ultimate (RC1 & 2) is one of the "premium" versions it would explain why you're getting a slow response when using it.
Vista Mem Use - Idle
Vista Mem Use - Company of Heroes
I thought I'd drop a couple of pics in to support my point, CoH is running with all settings on high but only 20 or so units at the start of a campaign map so it is not indicative of "full load", still it is enough to make me consider 3GB of ram.
MICROSOFT
Some features available in the premium editions of Windows Vista—like the new Windows Aero user experience—may require advanced or additional hardware.
A Windows Vista Capable PC includes at least:
A modern processor (at least 800MHz1).
512 MB of system memory.
A graphics processor that is DirectX 9 capable.
A Windows Vista Premium Ready PC includes at least:
1 GHz 32-bit (x86) or 64-bit (x64) processor1.
1 GB of system memory.
Support for DirectX 9 graphics with a WDDM driver, 128 MB of graphics memory (minimum)2, Pixel Shader 2.0 and 32 bits per pixel.
Being as how Vista Ultimate (RC1 & 2) is one of the "premium" versions it would explain why you're getting a slow response when using it.
Vista Mem Use - Idle
Vista Mem Use - Company of Heroes
I thought I'd drop a couple of pics in to support my point, CoH is running with all settings on high but only 20 or so units at the start of a campaign map so it is not indicative of "full load", still it is enough to make me consider 3GB of ram.