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What is my bottleneck? Answered

I just recently built a new gaming machine, and have been running into a bottleneck issue. I was wondering if anyone could give me some advice. 

My Specs:

Windows 7 Ultimate
MSI GD-55 Z-77a Motherboard
Intel i5 3570k OC 4.2 Ghz
Radeon HD 5770 x2 (Crossfire)
16Gb (4x4) Corsaire 1600Mhz RAM
1 Tb 7200rpm Western Digital HDD
850w Coolermaster PSU

I have downloaded the most recent AMD drivers and Crosssfire Profiles.

The problem I am having, is that I almost never see anything in my computer running at max while gaming. I will usually have my GPUs running at around 60-70%, and none of my CPU cores running higher than 50-60%. 

The first thing that came to my mind was temperature. However my CPU never gets hotter than 65c, and my GPUs never hotter than 80c. 

The other thing that I thought of was a possible lack of power. But 850w is at least 40% more than recommended for my system specs. To test this, I did a CPU benchmark, and a GPU benchmark at the same time, both hit 100% usage, and my computer did not lose power. (nor did anything get too hot)

After ruling Temperature and power out, I thought maybe it was my RAM. However, I have read multiple places that it is nearly impossible for any game to max out quad channel memory bandwidth. I have more than enough of better-than-average RAM, storage isn't the issue. So I doubt its my RAM. But I am no expert.

I then ran "Windows Resource monitor" to watch my HDD Disk usage. While gaming, nothing transferred more than a couple Mb/S. The specific specs of my HDD include a 64MB Cache, and a  6.0Gb/s Data transfer rate. My Motherboard also supports 6Gb/s Transfer rates. So I doubt its my HDD.

I know my GPUs are 2 generations old, but if they were the bottleneck they would be running at 100% (or at least higher than 80%)

Now I don't know what to think, except that its maybe software related. But I cannot think of anything specific that would do this sort of thing.

Any suggestions?



If your doing heavy gaming and none of the hardware is maxed out that's a good thing. It shows your hardware can more then support the games your playing. A bottleneck would be when your GPU isn't running at full speed but the CPU is and your frame rates won't go above 30 in the game.

So unless your not getting the performance you expected and things are not running at full speed then you don't have a bottleneck of any kind.

That is exactly what is happening. For instance in crysis, I get about 40-50fps, where my gpus are only running at 75%.

I guess I just don't understand why it wouldn't throttle everything up until something hit max. I suppose the best analogy for my thinking is a "Limited Reagent" Chemistry problem.

Thank you for the reply!

Bear in mind that the human eye doesn't perceive more then 30FPS. Anything beyond that you can't really tell the difference. Though many swear they can tell the difference between 60 and 100.

Part of the limitation is the crossfire configuration. You get better overall performance with the 2 cards but each card isn't able to perform at its absolute best. If 2 older cards in CF/SLI are compared to a single newer card (where the combined specs of the 2 older cards are almost identical to the newer single card) The single newer card will always outperform the 2 older cards. There are limitations to CF/SLI that cause this. So if the choice is presented to keep your current setup or get a newer single card solution with the same specs, Go with the newer card.

Hehe, don't get me started on 30 vs 60.
I got the 5770s from my brother who upgraded the same time I did, I plan on getting a single gtx 670 within a year.

I didn't suspect the crossfire though, that very well could be the problem. I have almost no experience with it.

Ive wanted to debate 30 vs 60 with someone for a while. So let me at least say this. Even if we can't see more than 30fps, you can definitely feel it. For instance, if I were to play Metro2033 at settings that would put me at 30fps, and I were to flick my mouse, there would be a noticeable difference between when the mouse begins moving and when the rendering begins moving. Whereas, in counterstrike source, i get around 250fps; If I were to flick my mouse, the mouse would start and stop moving, but the difference between the mouse and the screen would be imperceptible.

Anyway :)... thanks for the reply!

If you don't need anymore help, please remember to mark your question as "answered" by crediting the person who helped you with a best answer (i.e. click the blue button, please). :-)

You're not using the full resources, things like temperature don't "throttle" things (they choke them to the point of things crashing if they do).
Look for a "3D benchmark" and see what that does. E.g. http://www.futuremark.com/benchmarks/


I use MSI kombustor 2.3. When bench-marking, I do indeed reach 100% usages. I was just wondering why gaming wouldn't do the same thing if the resources were avaliable.

You're lucky if your machine is ahead of the game, but have you turned all the graphics-settings (game) up to the most?
If it doesn't need your system-resources it won't use them, increased "graphics-quality" will push it more, but your machine may still have spare capacity.


The settings are maxed out. For example in Metro 2033, on max settings, I get about 35 fps on average. But neither gpu will exceed more than 80% usage. I think that mpilchfamily may be right, it could be the Crossfire that is messing with things. This is my first crossfire setup ive ever seen, I wouldn't be surprised if it didn't act the same as a single-gpu setup. Crossfire probably adds more complexity than a 1 + 1 setup.