This computer "should" run the game fine. Right?

[kitgyrl]

So I built a new 'puter, specifically to play Sims 3 (and be a sniper on the battlefield...but that's another topic). 
I have installed everything and updated everything including Windows and my graphics drivers. 

The game will load fine (legit copy, vanilla).  However, beginning at the aerial town screen the screen will freeze (sound will continue uninterrupted) for approx. 10 - 15 seconds.  That is immediately followed by a black screen for about 3 - 5 seconds.  When the screen does come back, everything functions normally but this behavior repeats at random intervals as I continue in the game. 

This is a brand spanking new build so I don't have any previous history to base it off of for this computer but the system specs are:

Windows 7 Ultimate 64-bit
Intel Core i5 750
MSI P55-CD53 Motehrboard (Intel P55 chipset)
Visiontek ATI Radeon 4850 1gb
OCZ 4GB DDR3 1600 (PC-12800) Gold Low Voltage CL8 Memory (2 2gig sticks)
Thermaltake TR2 500W Power Supply

Quick note, I tried a different video card as well as rolling back to Vista and I am getting the same issue. 

um um um  I think that's it.  Like I said, I believe this setup "should" run it fine. 
Any suggestions or help are much appreciated.

[KawaiiMiyo]

O.o I'm no computer expert. but I have the ATI Radeon 4670 1gb, and my computer (Amd athlon dual-core) only has 2.1gb DDR2 ram  .. So my specs seem a bit lower than yours, yet I'm able to run TS3+expansion with the graphics on the highest settings, with very little to no visible lag. I receive no lag on the aerials either...

      The only time I experience any lag, is if I have the number of detail lots over 2-3 (I keep at 1 to be safe)  or right after I've explored an entire huge dungeon, with such a large map and so many items, i notice a couple of skips here and there, not enough for me to really care about it or notice it very much though.

[GnatGoSplat]

That should be more than good enough.  Run some diagnostics like MEMTEST86 and your favorite CPU tester (i.e. HotCPU, Prime95, etc) to make sure everything is working properly.  Also try CPUID HW Monitor to make sure the CPU and GPU aren't overheating.  Perhaps the CPU cooler isn't on quite right.  It's rare, but also sometimes you just get bad parts.

[Grimma]

Does your computer run any system-intensive (or even moderately intensive) background applications while you play TS3? Something like an over-zealous antivirus could cause the random lags.