Higher FPS with lower CPU speed? WTF

nightsilencer

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Oct 30, 2008
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Hey guys, I have a very weird issue happening with my computer right now.

I get higher frame rates when my CPU is on "Max Power Saving Mode" which basically underclocks every possible component to reduce power comsumption. I use this mode to surf the web, listen to music, watch movies, etc.

I usually play my games with FRAPS on (call me a frame rate freak) and I caught this "problem" only by chance. I started playing Dead Space and forgot to put my PC into "high performance" mode which basically puts the CPU at it's stock frequency.

I usually get around 40-45 FPS with everything maxed out, and I was already used to that constant frame rate. To my surprise, this time when I was playing, I notice a significant boost on my FPS; it jumped to around 55-60.

I was left wondering what had happened, I checked the visual settings and everything was maxed out @ the same resolution.

until I noticed my CPU was only working @ 1.7ghz (remember, is was on power saving mode). So I tested and retested and got the same results... with higher CPU speed I lose FPS... with lower speeds... I get higher FPS. WTF is going on? Is this some kind of new phenomenon? Like reverse bottlenecking or whatever...

any idea what it might be?

For reference, here are my specs:

Intel E8400 @ stock (no need to OC it right now, still plenty of juice left on it with stock speeds)

GF 8600GT (does not require aditional power, just what comes from the PCI-E bus)

Asus P5Q Pro

2x2GB Transcend RAM 800mhz

Deer (generic?) 480w PSU.... it came with my case.


And here are the pics of that happening with Dead Space. Also IT HAPPENS on other games, so I just put Dead Space pics as an example, since it happened on every game.

Dead Space @ stock CPU:



Dead Space @ throttling CPU:




The difference in FPS might not seem significant here, but believe, in some cases it goes as far as 15 FPS. What the hell is wrong with my PC? :|


 
I agree that is really weird. I would also check the tmps and try another game. Might be a bug in the game since it is new and all.

On the recent THG tests with Core i7 fore multi GPU setups, one game qith 4 HD4870s @ 1920x1200 was doing horrible. Then they added 8x AA and the performance got better.
 

Zecow

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Oct 29, 2008
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I agree with the previous poster.. I think the PSU can't cope with the requirements. Although that setup will consume no more than 300watts... Its not a quality PSU.
 

amdfangirl

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I don't think I've ever heard of 'deer'. If it came with your case too...

Quality PSUs can go beyond their limits whilst bad ones do not. I once had an Eagle (now bankrupt) brand PSU rated at 350w and a Thermtake rated at 300w. Difference? Well the 350w wouldn't boot with my BF's gaming machine but the 300w did. BTW, the 350w is not faulty, it works with my HTPC.
 
^The biggest difference there is that it didn't maintain a good temp and wasnt able to put out near its peak wattage. Probably was only putting out about 200-250w. Thermaltakes are great PSUs.

My old Thermaltake Xaser III came with a 420w Thermaltake PSU, back when they were younger in the PSU market. It was able to run all 7 case fans, the LCD screen, a 3.4GHz EE P4 Northwood, 2 SATA HDDs, a DVD burner and a ATI Radeon X850XT and acted like it was nothing.

Nice catch though fangirl. Even though its rated for 480w (probably peak when at below 40c) it will probably not get enough to keep the CPU and GPU happy at full speed so the GPU throttles due to lack of power.

My suggestion to the OP, get a 500w Thermaltake or Corsair PSU thats 80 Plus Certified. Those are the best and they are not that expensive.
 

MaDMagik

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Oct 12, 2008
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Had a similar situation few years back on my ancient machine when playing quake3, the 960x720 resolution would bring higher framerate than 800x600 or even 640x480. Till this day i have no idea how was that possible