I'm running windows 7 with 2G of RAM, and in all cases 64bit is *much* faster than the equivalent 32bit build. Really, your system isn't terrible so to speak, but you definitely need more than 1G of RAM. Seriously, if you get 2G of really fast RAM in there, you'll have more of a performance boost than you would think, even outside of Dolphin.
Also, make sure you're turning on Dual Core, even though you've only got a single-core processor. The multi-threading benefits are still there because of the way the windows kernel can handle the process rotation.
Oh: Since you're low on RAM and Windows Aero consumes a bit... much... try turning it off. Just go into your control panel for Personalization and kill the "enable transparency" option, or enable one of the basic (like Classic) themes in the bottom of that list. It doesn't affect a thing for me, but on lower RAM systems it might make a difference. (XP doesn't do the whole hardware accelerated desktop thing, which might be the main difference, as Win7 is pretty lightweight on memory otherwise. Unlike Vista, which just generally sucked.)
Also, make sure you're turning on Dual Core, even though you've only got a single-core processor. The multi-threading benefits are still there because of the way the windows kernel can handle the process rotation.
Oh: Since you're low on RAM and Windows Aero consumes a bit... much... try turning it off. Just go into your control panel for Personalization and kill the "enable transparency" option, or enable one of the basic (like Classic) themes in the bottom of that list. It doesn't affect a thing for me, but on lower RAM systems it might make a difference. (XP doesn't do the whole hardware accelerated desktop thing, which might be the main difference, as Win7 is pretty lightweight on memory otherwise. Unlike Vista, which just generally sucked.)
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