High but not Highest End System for FS9, with random stutters

I decided I could not afford a new computer completely, but for a alot less, I can get a newer graphic card and CPU for my current system.

I replaced my AGP Saphirre radeon X1950 Pro to a HIS Radeon HD4670 which has 1gig of DDR3 memory and a faster clock speed compated to the X1950 with has only 512MB of DDR3 memory and a slower clock speed.

Then I replaced my 2ghz dual core CPU with a 3.06ghz dual core CPU

when I did that I notice that the BIOS did not detect the curreny CPU, so I went here to see what BIOS update would be needed.

http://www.asrock.co...al-SATA2&o=BIOS

and installed the windows flash version 2.10 which indicatates a CPU code update

when I rebooted after the flash, the finally detected the correct CPU of a 3.06ghz

when I tried my flight sim for the first time I noticed a huge increase in frames, which was what I expected, it was smooth for a bit, then the stutters kicked in. I thought it could be active sky 6.5, but I tried it with clear weather and multiple planes including the default cessna and the stutters are there. The frames never drop below 30 where I have them locked when I get the stutters.

Wtih my old video card and 2ghz CPU I did not ever get this stutters...my frames where not as high and I had them locked at 30 frames too, but it was still stutter free flying. So I dont understand why this is happening when I have faster hardware. I did not update the bios on my mobo to the highest version since it seem like it did not need it. The CPU code was the one that got my attention.

its more like an elastic band stutter...where the sim stutters every second, then the plays "catchup" before the stutter hits again. really annoying.

I dont seem to get the stutters in windowed mode, but dont like flying in windowed mode, only in full screen mode.