First sorry for my bad English , it's not my native language.

I just upgrade VGA from HD 5770 to HD 7970 Ghz Edition but no performance increase.
So I feel stupid and wonder if it's CPU bottleneck ?

Test System Setup
CPU - Intel Core i5-2500K 3.3GHz 4cores 4threads
CPU cooler - Coolermaster Hyper 212 Evo
M/B - Biostar tZ77xe4
RAM - Kingston 2 x 4GB DDR3 1333 CL 9-9-9-24 commandrate 1T
VGD - His HD 7970 IceQ x2 (flash bios to GHz Edition) 1050core 1500mem
SSD - Plextor M5Pro Extreame 128GB
HDD - Western Digital Blue 500GB
PSU - Nox Urano II 530W
OS - Windows 8 64 bit
Sims - All Expansions Patch 1.55
Graphics Setting - Max Everything @ 1360x768 resolution , screen refresh rate @ default

I use THIS house for benchmark http://www.thaithesims3.com/topic.php?topic=113958
You can see it is 64x64 lot with tons of furniture , It's good for stress your computer.
If you want to download it click here http://www.4shared.com/file/BA60piC...ni_Pattaya.html or http://www.mediafire.com/download/i...ttaya.Sims3Pack

And I use FRAPS to record FPS for 1 minute.


Result

4cores stock clock : load game 49.59 secs / load house 1.30.75 min
Frames: 2394 Avg: 39.900 - Min: 9 - Max: 114

3cores stock clock : load game 49.11 secs / load house 1.27.49 min
Frames: 2383 Avg: 39.717 - Min: 10 - Max: 113

2cores stock clock : load game 49.02 secs / load house 1.34.13 min
Frames: 2077 Avg: 34.617 - Min: 7 - Max: 101

1core stock clock : load game 1.09.44 min / load house 2.21.46 min
Frames: 892 Avg: 14.867 - Min: 4 - Max: 31

-------------------------------------------------------------------------------------

4cores 4.0GHz load game 44.59 secs / load house 1.20.55 min
Frames: 2929 Avg: 48.817 - Min: 11 - Max: 121

3cores 4.0GHz load game 43.90 secs / load house 1.16.49 min
Frames: 3179 Avg: 52.983 - Min: 10 - Max: 128

2cores 4.0GHz load game 44.25 secs / load house 1.21.68 min
Frames: 2830 Avg: 47.167 - Min: 12 - Max: 122

1core 4.0GHz load game 1.04.59 min / load house 2.21.86 min
Frames: 1012 Avg: 16.867 - Min: 8 - Max: 36

-------------------------------------------------------------------------------------

4core 4.5GHz load game 41.89 secs / load house 1.11.66 min
Frames: 3666 Avg: 61.100 - Min: 13 - Max: 136

3core 4.5GHz load game 39.58 secs / load house 1.11.50 min
Frames: 3717 Avg: 61.950 - Min: 14 - Max: 136

2core 4.5GHz load game 40.88 secs / load house 1.15.67 min
Frames: 3109 Avg: 51.817 - Min: 15 - Max: 122

1core 4.5GHz load game 57.27 secs / load house 2.01.45 min
Frames: 1097 Avg: 18.283 - Min: 6 - Max: 39

-------------------------------------------------------------------------------------

conclusion : As you can see Sims 3 REALLY NEED very high single-thread performance CPU
from stock clock to 4.0GHz framerate improve by 22.34% load time improve by 12.66%
from 4.0GHz to 4.5GHz framerate improve by 25.16% load time improve by 12.40%

total improve from stock clock to 4.5GHz framerate improve by 47.5% load time improve by 25.06%

On the other hand Sims 3 don't need good multi-thread CPU (such as AMD FX-6300 FX-8350 or Intel i7)
From 1 core to 2 cores Performance improve by large margin.
But form 2 cores to 3 cores performance improve by just 14%.
And 3 cores to 4 cores no performance improve even it's hurt a bit.

My suggestion if you want to play very large house and expect no lag.
if you have money buy i5-4670K and overclock it as much as possible (4.5-5GHz).
if you tight on money i3-3220 will do the job .
For VGA something beyond HD 7750 or GTX 650 will OVERKILL for Sims.

How did you disable cores for the test?

Set affinity in task manager.

Is the game installed on the SSD or the HDD?
And dude! HD 7970 and not even on a 1080p resolution? And 100++ frames (is that per sec) on Sims? Don't burnout that GPU before you use it to its full potential!

Is your card model listed in the GraphicsCards.sgr? You need to inform Sims 3 of the new card, if it is not found.

Game Help:Getting new graphics cards recognized by the game^wiki
Q&A: Getting new graphics cards recognized by the game

Other than that, Sims 3 is a 32-bit program that probably does not utilize multi-core processing nor multi-threading well, if going by the .sgr rules and all the inherent issues within the game. Which is why our SysReq never did suggest to build/buy a machine that cost upwards of US$2500 (with 27" monitor) and beyond. It is just a waste of money (added to a strong GPU on a small resolution). But if SIms 3 is not the only game you play nor the only intensive application you run, than the high cost is really to support the other work, and not just Simming, then it is your money your toy. To each his own.

Windows and Sims install on SSD
Yes it is frame per second.

That house is very limit FPS by CPU bottleneck even 2500K @ 4.5 still lag and have very low minimum framerate like you see.
But normal house such as 40 x 40 lot , 2 bedrooms FPS is overkill to 200+.
I guess if sims 3 can utilize multicore well it should have stable framerate (like modern games on DX11) Hope sims 4 is 64bit app in DX 10/11

Do you recommend any program to force vsync ? (I want stable 60FPS. not max 100+ min 10- )
I try catalysy control center , radeonpro , virtu MVP virtual vsync , FPS limiter but nothing work

Don't worry my card recognize by game

=== Rating info ===
GPU: 5 GPU Memory: 1 CPU: 4 RAM: 4 CPU Speed: 3301 Threading: 3
Adjusted CPU: 4002 RAM: 8157 Adjusted RAM: 7645 Cores: 4
=== Graphics device info ===
Number: 0
Name (driver): AMD Radeon HD 7900 Series
Name (database): AMD Radeon HD 7900 Series [Found: 1, Matched: 1]

Sims is not my only game I play , the other is GTA IV dirt3 and wait for the upcoming command & conquer 2

Finally i7-3770K @ 5.3Ghz Save game in just 10secs !!!

http://www.youtube.com/watch?v=2opucq6nF5w

FPS limiter didn't work? I have a 7950 and I use the limiter [and 3booter, but that's something else] from MATY and it keeps it at a stable 30 FPS. Did you follow all of the instructions for proper install?

LINK, just in case.

This is all I can contribute to the conversation, but you really should get something to stabilize and cap your FPS because TS3 can, and most likely will, tax your new card until it overheats and/or dies (as I'm sure you already know). : /