Mysterious performance drop.

[Refreshment]

Good day Anandtech community.
Specs:
Phenom II X3 705e
MB A9K2GM-FIH
4GB Kingstone DDR2
Radeon HD 5850
Multi boot with Windows 64 bit.

I have this strange behavior with the PC. Some times I get performance drops in games for no apparent reason. For example, I get a frame rate drop in Dirt 2 of 15 fps and in Crysis like 5 fps. At one time I thought this was due to a recent RAM change, but it isn’t.
I do an Overclock to the graphics card using afterburner with no voltage increase, but I don’t think this is the issue since so far there hasn’t been any graphics corruption that I could see. Plus I did run the card at stock settings and I suffered a bigger performance drop.
Some times I get the normal performance even for days and then suddenly it drops.

Any guesses?

 

[Lanyap]

What was the recent RAM change?

Did you run a memory test/diag after the change?

 

[Mr. Pedantic]

Do you mean the performance drops seemingly spontaneously during playing, or between levels, or between closing and restarting the game, or on certain days? And with the drop, is it still smooth, or does it become jerky and unresponsive as well?

 

[Refreshment]

What was the recent RAM change?

Did you run a memory test/diag after the change?

First i thought it was the RAM, but then it started working even better than with the previous RAM. As for memory diagnostic, just used the default windows memory test.

Do you mean the performance drops seemingly spontaneously during playing, or between levels, or between closing and restarting the game, or on certain days? And with the drop, is it still smooth, or does it become jerky and unresponsive as well?

I would say its on certain days, so far it hasnt happen in game. For example if i get good performance in Dirt it stays like that the whole gaming session.

Regarding the drop, no, it isnt jerky, glitchy or unresponsive. Lets say in a "good"performance day i get 60 fps in DX11. In the "down" performance day i get 45 FPS but its smooth and constant. Image quality wise its the same.

 

[Mr. Pedantic]

Then is there any kind of behavior that correlates with those days where performance is 'bad'? Like, maybe you hibernated instead of completely shutting down, or you used some other kind of program that day? Or are there specific days of the week it happens?

 

[Refreshment]

Then is there any kind of behavior that correlates with those days where performance is 'bad'? Like, maybe you hibernated instead of completely shutting down, or you used some other kind of program that day? Or are there specific days of the week it happens?

Sadly i haven´t been able to make any correlations. Not specific days either, right now the drop in performance has stayed close to a week.

 

[Refreshment]

Did a quick check with GPUz, it says the PCIe adapter its working at 4x. Any ideas how could i set it to 16x?

 

[Refreshment]

Like expected, the PCIe bus speed was the culprit. Operating at 4x, it translates into a performance lost of 15 fps in Dirty 2.

Yet the problem is not entirely solved. When I reseat the card it was operating at 16x, but I soon as I screwed to the chassis, it moved so its operating now at 8x. At least I could take comfort in that the reason for the throughput drop is known now.

It also explains why performance was normal for days or even weeks just to suddenly drop again without apparent reason. Every time the PC was moved it most have flexed the motherboard causing the card to move.

Thanks for everyone that gave advice and share their thoughts. Now lets see how can I correctly fix the card.

 

[jdwright]

I also have a phenom II x3 and after adding a new fancy video card, I realized I wasn't getting the performance I expected. I was very focused on the video card and managed to overlook the clocked heatsink on my processor. It was overheating and throttling back - causing the videocard to perform poorly.

Probably not your problem, but thought I would mention it =).