You could also try third party drivers or making sure you have the newest drivers. I have a computer laying around with a athlon x2 250(1 step from yours) and gts 250. I didn't notice any visual issues and for the most part it was around 130 percent minus the stutter from shader because i didn't bother with ubershader or skip drawing. using 5.0.16101 and windows 7 by the way. I did have a message about buffer storage and direct 11 did also message since it was windows 7 but also work. For the record I know the gts 250 is good amount faster then the ATI Radeon HD 3450 but it feature set would be similar. For people who might think so this system isn't use for dolphin but for older windows xp games. Windows 7 is dual boot to allow for modern file sharing support since xp doesn't support 128 bit encryption that is used in windows 7 or newer and I don't want to reduce file sharing security for just a retro computer and for some game that have direct 10 support.
I'm not recommend getting a gts 250 to run dolphin either. I would recommend a new computer for the most part. This was to only compare and see if a 2007-2009 era nvida would have similar issues.
I'm not recommend getting a gts 250 to run dolphin either. I would recommend a new computer for the most part. This was to only compare and see if a 2007-2009 era nvida would have similar issues.