PC meets game requirements but performance fluctuates.

[Tabob]

My computer does the same thing no matter what game i play. even if my pc meets or exceeds recomended requirements, performance fluctuates. it will start of running awful FPS like 5 or less. IF this is due to just rendering etc i would understand, however after 5 or so minutes, sometimes longer, it steps up to 45-60 FPS for 30 seconds or less then drops right back to 5. Example of a game im playing now is Dungeons and Dragons Online. Not a very hardware intensive game. My wife plays it on a gateway laptop thats 4-5 years old with no issues. The game even recomends Very High graphic settings based off my hardware. Any ideas as to whats causing the issue?

Also, Speedstep on or off makes no difference, cpu temp under load is only 47C. And adjusting settings in game for better performance makes no difference.

PC specs

Windows 7 Profesional x64
Asus P5N73-AM motherboard
Intel Pentium D 940 3.2GHz CPU no OC
4G DDR2 333MHz ram
Nvidia GTX 560 ti Graphics card
450W PSU
CPU Cooler + 4 case fans

 

[Tibbs01]

Most 560 Ti's require at least a 500w PSU, so that would be the first place I would look (assuming you have already updated drivers etc.). What is the make/model of your 450W unit?

 

[shotgunz]

That pentium D is 8 years old and does not have enough cpu power to run a 560 ti.

Download CPU-Z and GPU-Z and give us a screenshot showing cpu and gpu usage while in a game. Example:

 

[tiny voices]

The PSU is probably not the problem, as it would not affect performance, simply just turn the computer off if there was not sufficient power.

The CPU being too weak is the issue here.

 

[Tabob]

Yeah PSU is a pretty debateable subject. i dont really get how a good GPU is causing my CPU to have issues though.....
Hows this?

 

[shotgunz]

Your CPU and GPU exchange infomation with eachother, so if your cpu is slow, it won't be feeding your gpu enough infomation fast enough to let it run fast.

Example of what underpowered CPU's can do to a GTX 680:

 

[J_E_D_70]

The CPU does all the front end work to feed info to the GPU, sometimes is tasked with processing sound and physics, etc. The CPU is just not up to the task of any more.

Bring up Performance tab of task manager and stretch it out. Play a game that causes problems. When you hit a slowdown, tab out or shut the game down and look at the results. I bet you'll see your two core spiked all the way up - when that happens, there are processes that are waiting their turn and that will cause the game to get choppy since the GPU isn't receiving the info it needs to render the frames.

 

[Tabob]

But even if my cpu is over the 1.6GHz dual core requirement it causes issues? Is there anything i can do other then upgrade to help it out

 

[shotgunz]

Yeah PSU is a pretty debateable subject. i dont really get how a good GPU is causing my CPU to have issues though.....
Hows this?

Ops, Sorry, wrong program, it's coretemp, not cpu-z.

But in the gpu-z window in gpu load, you can see your gpu barely has any load on it, meaning your gpu was not working very hard. Would you mind showing us a picture with coretemp instead of cpu-z?

 

[shotgunz]

But even if my cpu is over the 1.6GHz dual core requirement it causes issues? Is there anything i can do other then upgrade to help it out

The Ghz rating on a CPU is how many cycles a cpu goes through in a second, not it's performance. For example:

This is the Pentium D 940 which is a dual core 3.2 Ghz CPU compared to a more up to date also dual core 3.2 Ghz Intel Pentium G3420

Look at the scores of these two processors from Passmark's CPU benchmark.

Edit: Unfortunately, there are much fewer graphics settings you can change to alleviate CPU bottlenecks compared to gpu bottlenecks. One of the graphics options to lower cpu usage is to lower the amount of physics happening.

 

[tiny voices]

Your CPU is bottlenecking the GPU. It is simply not powerful enough to keep up with your GPU, therefor the GPU cannot even work to its full potential.

It does not matter that the CPU is enough to run the game at lowest settings. It is not powerful enough for your GPU. Plain and simple.

 

[Tabob]

Okay so this being the case, is there a way to restrict my gpu to help out? Or what else can I do other then dishing out money for a new motherboard and intel i5 or i7 processor?

 

[tiny voices]

There is no real way to fix it besides lowering the settings to lowest settings in games or getting a new CPU. It doesn't have to be an i5. Something like an fx-6300 would work perfectly with that GPU.

 

[Tabob]

My motherboard has an intel LGA 775 socket so choices are limited without getting a new motherboard, CPU and ram (DDR3) I take it theres no way to "dumb down" my gpu to better meet my cpu?

 

[tiny voices]

You can try playing at lowest game settings. If that does not work, you need a new CPU/ motherboard/ RAM.