What is causing my low FPS with ATI 4870

k1shotz

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Sep 22, 2008
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I have a gateway gt5670 with a upgraded power supply and an ATI 4870. I tried to play Crysis and whoa, it was not good. Ive seen videos of Crysis gameplay with the 4870 and the graphics were great. Mine, nope. It had to be something with my CPU that was causing this. Here are the specs of my comp:

Windows Vista Home Premium (32-bit, SP1)
AMD Phenom 8400 Triple-Core Processor 2.1GHz (3MB L3 Cache, 3600Mhz Bus)
ATI Radeon 4870
3GB DDR2 Memory (2 x 1GB, 2 x 512MB, up to 4GB)
320GB 7200rpm Western Digital Hard Drive
600W Power Supply

Im assuming it is my processor, but I just want to make sure.
 
Crysis is very CPU demanding. Phenoms are not 'the best', but you can still see good performance.

What I've experienced, and articles I've read, all seem to agree that to unleash your video card's true performance in Crysis you need to hit 3Ghz + with your CPU.

My quad core is stock 2.4Ghz, and when I bumped it to 3Ghz and 3.2Ghz I noticed some pretty good FPS gains.
 

spoonboy

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Oct 31, 2007
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Your very cpu limited. I saw some big gains in fps on my old 7900gt in crysis when i went from 2.4 to 2.8ghz on my intel dual core (e6300), now ive got a 4870 and my max cpu overclock of 3.1ghz still seems like not enough to get the best out of the ati wonder card (I luv my 4870 lol). Crysis doesnt really use lots of cores so having a 3 core cpu wont help as mkuch as you might think. With a 4870 running crysis in dx9 mode you should be able to reach these settings: (my highest playable settings)

resolution 1400x900
no AA
no AF
Physics - high
sound - high
textures - high
ALL OTHERS 'hacked' to very high through changing the 'cvar' files in the crysis directory,

Averaging about 30fps (except the harbour level where my crappy small 2gb of ram and slow 250gb hard drive juct get overwhelmed, then about 28fps) with card overclocked slightly to 800 mhz core, 1000 mhz (4000mhz effective GDDR5 speeds) video ram. In short your close to maxxing crysis at 1400x900/1280x1024 with this card and a FAST cpu.
 


Its more CPU speed depndant though.

What he needs to do really is OC his CPU or get a faster one. 2.1GHz is not fast enough for a game like Crysis.
 

Ryun

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Oct 26, 2006
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That's your problem.

You've got the TLB errata fix on since you're using Vista SP1, which creates a performance penalty (usually 10-15% but can be more). The errata was pretty overhyped, and you'll probably never experience it, so you should be able to run this program from AMD here to disable the fix.

When you install the program in the upper right hand corner the button should be green. To be honest I'm not too familiar with the software, but you should be able to change it from green mode to yellow, or red mode. Get it to either red or yellow mode and you will disable the fix. You will have to do this everytime you load windows.

Also, disable Cool'n Quiet in your system's BIOS (or, in the AMD overdrive, but again you have to do it everytime you start windows.) as there have been some performance issues with this as well.

You won't get a massive increase in performance but it should be better. Also, play on the highest resolution you can so you can take some of the load off the processor and more on to your GPU.