Framerate drop after 10-20 minutes of gameplay

[aftershave]

Hi, new to the forums.
I am currently gaming on my Macbook Pro 2010 15 inch i7 512 VRAM GT 330M
After starting any game for 10-20 minutes, the frame rate abruptly stops to a crawl. Usually from 40 fps to single digits. There is also a noticeable drop in smoothness outside of the game, scrolling and typing feels sluggish, the UI in general feels unresponsive.
At first I suspected a problem with my CPU or my RAM, but further investigation revealed that during said episodes, I have abundant free RAM and much of my CPU is free as well. So this only leaves either the GPU or the OS to blame.
These frame rate issues come and go, they come for at most a few weeks at a time, and then just disappear for a few more weeks, only to come back at some random time later. I am very frustrated, I cannot game when I want to, please help.

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Edit:A quick google search revealed that others are also having said issue
https://discussions.apple.com/thread/3677057?start=0&tstart=0
Also shows the issue was also present in 10.6

 

[pragmatous]

Are there any OS updates?

 

[aftershave]

It's fully updated

 

[musty345]

Try installing smcFanControl and make sure your mac isn't overheating

 

[Bear]

Depending on the game, frame rate issues can be caused by network issues. This particularly includes MMOs.

 

[aftershave]

The same problem occurs on offline games. I do have fan control software, when the game is running I have the fans at 6000 RPM, the temperature is usually around 75-80. But strangely, the first time I open a game after each startup, the game runs perfectly despite the temperature, after the drop, the game immediately gives 10-20 fps at start if you restart the game. The temprature of the laptop is the same before both startups of the games.

 

[pacman7331]

Yea man I was having this problem on my earlier 2009 MBP. It is probably just the game you are playing is not well designed for mac. I was playing Prince of Persia Sands of Time, after about 10-20 min like u said the game would become very very slow. I do not think I ever solved the problem, In tried many OS reinstalls of lion, snow leapord and leapord. All had the problem. I do not think it is a hardware problem, as I suspect if you play the game in windows it would work fine. Allot of GameTreeMac translated games just do not work well, I also noticed spore had the same problem. Starcraft 2 while able to run consistantly, in windows ran at least 2 times better. Its sad but people who put out mac and pc games usually botch the job on mac. Its very frustrating.

What is even more frustrating is the tendency for high performance games to overheat the MBP causing it to eventually suddenly sleep or power off in Windows. That to my mind is just disasterous and makes the MBP itself a peice of garbage. Dunno what to say but either try your game in windows and find some way to keep it cool, or buy a PC. Because ive posted here on this fourm about the heat problem, and ive searched the web, many people have the problem, there are no solutions comming from apple, and those with MBPs who have not had it happen, dont like hearing about it.

 

[204353]

I've just noticed something rather strange while playing Diablo 3 on my MacBook Pro (specs in signature)...

I kept experiencing a huge performance drop after just 5 minutes or so of gameplay. I didn't have this problem when I first got the game, but the weather here in the UK has been unusually hot this week. I figured it was overheating the Mac, so I just started running the game in a window so I can keep an eye on the CPU temperature (via iStat Menus).

The CPU temperature (and GPU temperature) was much lower than its normal peak, around 70-75 Celsius rather than 85-90 Celsius. I checked the power brick/adapter thing and noticed that it was very, very hot! Because of this, I tried detaching the MagSafe connector from my Mac... and the performance shot up massively! The CPU temperature started climbing to its normal levels as well.

This bizarre behaviour suggests to me that the computer was throttling its power in response to the power supply overheating, not the Mac itself.

I'm now gonna try placing the power adapter on a cooling pad to see if it helps at all. It may be worth trying unplugging the charger if you're getting gaming performance drops.

 

[204353]

Actually, it seems that the power supply's temperature doesn't affect performance (I let it cool down before plugging it in again). However, the performance is still much slower when plugged in and super fast when unplugged... It's almost like the throttling is the wrong way round, using more power when on battery than when plugged in!

I'm confused. Any ideas?

EDIT: It appears that I've solved my particular problems; my fans/heat sinks were clogged with dust. I opened up the machine and used an air pump to blast out the clogged dust and it's made a HUGE difference to the performance of the machine. Diablo 3 now runs smoothly at all times.

If you've got the guts to open up your Mac, it may be worth checking your internal fans and heatsinks for dust build-up.