I was already afraid this topic is could go wrong direction when many will report "strange stuttering issues" thinking "yeah, that's that micro-stuttering. If you're gaming 200fps there no way it could be micro-stuttering. Check your systems people! As far as I know there's no crossfire support in NFS Pro Street so it's not correct way to analyze anything related to this issue. Please check this with Crysis. It's good example because game plays just like on single card, even framerate looks very good. If you can't notice it, then you cannot notice it any other game. I really think when playing Crysis, my minimum framerate is actually current framerate (1680x1050&noAA/AF). At least that's how it feels.

Here's list of crossfire supported games in catalyst 8.1:

*Stranglehold.exe
3DMark03.exe
3DMark05.exe
3DMark06*.exe
3DMark2001.exe
3DMark2001SE.exe
3dsmax*.exe
AcroRd32.exe
ACTOFWAR*.exe
AFR-FriendlyD3D.exe
aquamark.exe
ARX.exe
Battlefront.exe
BattlefrontII.exe
battleofthegods.exe
BF2.exe
BF2142*.exe
JustCause*.exe
BfVietnam.exe
Biademo.exe
Tiger 2004.exe
Bioshock.exe
BOS.exe
Breed.exe
BreedSPD.exe
cccprev.exe
chess.exe
CoD2?P_s.exe
CoJ.exe
FEARXP.exe
Condemned.exe
Crysis*.exe
CT3.exe
DFX.exe Bia.exe
Driv3r.exe
DungeonSiege2.exe
Dwm.exe
legends.exe
Ehshell.exe
EiB.exe
episode.exe
EverQuest2.exe
Fable.exe
FarCry.exe
FEAR.exe
FEARspdemo.exe
FFXiBench.exe
FFXiWinBench.exe
fifa07*.exe
fsx.exe
FlatOutdemo.exe
CMR5.exe
FreeCell.exe
fs9.exe
game.dat
GodFather.exe
graw*.exe
gt.exe
GW.exe
gwdev.exe
H5_Game.exe
halo.exe
Hearts.exe
hellgate*.exe
HitmanBloodMoney.exe
hl.exe
hl2.exe
InkBall.exe
Inventor.exe
iw3mp.exe
iw3sp.exe
KingKong*.exe
KingKongDemo*.exe
LegoStarWarsII.exe
Lithtech.exe
LockOn.exe
LostPlanet*.exe
Mahjong.exe
Matrix.exe
MaxPayne2.exe
MaxPayne2Demo.exe
Minesweeper.exe
mm.exe
Gothic3.exe
mohpa.exe
Morrowind.exe
narnia.exe
nba2005.exe
nbalive06.exe
NFSC.exe
NFSC_demo.exe
nhl06.exe
nhl2007.exe
NWN2*.exe
oblivion.exe
PainGame.exe
Painkiller.exe
PandoraMultiPlayerDemo.exe
Pariah.exe
patriots.exe
pc_matador.exe
PCMark04.exe
PCMark05.exe
pol.exe
pop.exe
pop2.exe
pop3.exe
primarysurf.exe
PurblePlace.exe
R6Vegas_Launcher.exe
RaceDriver.exe
RD2.exe
RD2D.exe
RD3.exe Age3.exe
RelicCOH.exe
RomeTW*.exe
Sam2.exe
Scarface.exe
ShadowVault.exe
sims.icd
Sims2.exe
Sims2EP1.exe
Sims2EP2.exe
SinEpisodes.exe
Snowblind.exe
Snowblind-Demo.exe
Solitaire.exe
speed.exe
Speed2.exe
Speed2demo.exe
speedDemo.exe
SpiderSolitaire.exe
SplinterCell.exe
SplinterCell2.exe
SplinterCell3.exe
SplinterCell4.exe
starwars_pc.exe
Suffering2*.exe
SupremeCommander.exe
Swat4.exe
Swat4SPDemo.exe
sweaw.exe
SwgClient_r.exe
TechDemo.exe
TestDriveUnlimited.exe
thrones.exe
Timeshift*.exe
TRAOD*.exe
tribesv_?pdemo_en.exe
trl.exe
TV_CD_DVD.exe
TW2004.exe
TW2005.exe
TW2007.exe
USM.exe
UT2003.exe
UT2004.exe
UT3*.exe
w40k.exe
Wargame-g4wlive.exe
white.exe
wic*.exe
WoW.exe
X2.exe
X2-Demo.exe
x3*.exe
XPANDRALLY.exe
XR_3DA.exe