New to overclocking

[Vay]

My specs:
Processor: Intel Core 2 Quad Q8300 @2.5 GHZ
Memory: 4 GB
System: 32 bit
PSU: XFX 650W
For the ATI XFX HD5870, newegg only lists that it has a 1200 MHz effective memory clock, while other lower priced GPUs have somewhat higher effective clock speed. Should I overclock the 5870? Or does it matter?

 

[Lmeow]

1200 MHz is meant to equal an effective 4800 MHz really, with GDDR5 you multiply your base speed by four. Overclock the HD 5870 if you feel you really need more performance, otherwise I don't see any point in doing so.

 

[Scanlia]

If your new to over-clocking, just use the Catalyst Control Centre for it. Even with the slider to the end, its not much compared to what other people have overclocked to...

 

[Vay]

The MSI 5770 HAWK has 4800 MHZ with GDDR5.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127490
Did they do the multiplication for 5770 and not for the 5870?

 

[wolfram23]

The MSI 5770 HAWK has 4800 MHZ with GDDR5.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127490
Did they do the multiplication for 5770 and not for the 5870?

So it would seem. Most people will talk about the speeds in terms that aren't multiplied. For example I say my 5850 is at 1200 mem overclocked, instead of 4800mhz. There's other reasons why the 5870 is faster tho like having more ROPs, shader processors, and a higher bitrate.

5870s should have a fair bit of overclocking head room. It can gain you 20% more performance or better depending how far you want to push it.

As mentioned, CCC offers some limited OCing that you should be able to attain no problem. Or you could get MSI Afterburner and OC it beyond that. It can also allow you to adjust your voltage if your cards allow it.

 

[Shirosaki]

Can anyone explain step by step how to use MSI Afterburner properly?

I've been googling it and all I get are vague guides about it and OCing your GPU.

Core clock and Shader clock are linked. Do you raise those first? When do you raise memory clock? Does memory clock have to be raised at the same time as core clock/shader clock or afterward? Does memory clock have to be OCed comparably to core/shader clock? (like a ratio or something that's good)

When do you OC voltage? I have a MSI 460gtx and the voltage can only be raised from 1.000 to 1.087. If you're trying to get the most out of your card, do you just raise voltage to max? And how hot is too hot for a GPU? What percentage is good for your fan speeds to be running at?

Also, I think I read somewhere that you should OC with Furmark running the stability test. Is that true? And is 15 minutes all you need to run it for to test if it's stable?

When you save your settings for your OC and restart your computer is it ok to just load back to those max settings without any increments?

Sorry for all the questions, but everyone just says you just slide a bar and it seems like OCing a GPU is a little more complicated than that.

 

[wolfram23]

It's pretty simple, you're overthinking it a bit...

You can start by OCing core or memory or both. I don't recommend both since it makes it harder to determine what caused something to go wrong (freeze/crash/blank screen etc). Generally making 25mhz increases is a good way to go. Test with FurMark, yes. I do only about 3 minute checks initially and then about 5 or 6 minutes when I really want to check stability. Basically, after 4 mins or so the temps should be leveling out, and temps (especially VRM temps) are a major issue. If FurMark is stuttering a lot or artifacts, stop the test and drop your clocks a bit. Artifacting sometimes requires a PC reboot to get rid of. If FurMark is stable for up to 10 mins let's say, then get to gaming but remember that games can stress GPUs differently and sometimes require an additional 10mhz underclock.

GPUZ is a good temp monitor since it will give you all the temp sensors not just GPU core 1. (IE: RAM and VRM temps too which are usually hotter than the GPU)

There may or may not be a sweet spot for core/mem speed ratios. The higher the better in both cases. Memory speed has a lot to do with anti aliasing and such. Testing it in FurMark, run 4xAA or higher. Core speed gives you raw rendering power. With 0xAA you'll see big differences from core OCing. In actual game performances, they use the memory and core a lot so you want both as high as possible.

 

[Shirosaki]

ok thanks. So what about voltage? Do you just max it out initially so you can overclock the highest? When you restart your computer the settings reset right? Is it ok to just raise them back to max without increments? And is it ok to be running Furmark while raising the clock speeds or do you stop Furmark, raise, then start Furmark? Also can I let my card go to 100 C and be ok?

 

[aznshinobi]

For the voltage, guesstimate. Use Kombuster and test for stability. Start off high then go to low. I went low to high but i perfer low to high more. 100C is way to high. 80C is to high. 70 is also pretty high already. But 70ish is a good temp. And yes settings reset after shutting the system down. And yes thats fine. increments are just till you get to a stable clock speed. and you should run furmark as you oc.

 

[wolfram23]

No no you don't just up the voltage first. You max out core speed at stock, one you get to a point that it crashes/artifacts, increase the voltage a tad (like 0.05V) and go up from there. You have to watch the GPUZ temps because, as an example, I've had my GPU stable at 985/1200 with 1.225V, but if I run FurMark for too long the temps hit 120C and it crashes - but only the VRM temps! The core temp is like 77C. It's a fine line between voltage and VRM temps.

 

[beelphegor]

Hi I am also new to OCing and using afterburner. I'm by no means trying to hijack your thread, I'm hoping perhaps these may be questions you are interested in having answered as well. I would like to know about artifacts, is this when the screen starts to frag?

I OC'd my msi 8600gts last night to see if I could get it to benchmark better for ffxiv. I did it in 10mhz intervals and ran the benchmark 3-4 times then upped it more. The temp seemed to stay in the 60s so i just kept pushing. I had increased my benchmark by about 300 points and was really happy that the temp was still only maxing at 68, and I couldn't see any fragmenting of graphics or anything really, just a slight stutter starting to form. I increased it 10mhz more and my screen just went black after about 30 seconds. I could get ctrl+alt+del to pop up the vista window, but when i hit taskmanager it would just go black again.

For future reference, is there a hot key for afterburner that will reset the settings so that when this happens I do not have to shut down the computer?
Why is it that i never saw any artifacts, but the screen went black? I would think artifacting would occur b4 that.

I never messed with the voltage, perhaps this might have something to do with it?

 

[wolfram23]

If you were OCing the memory too, you tend to see stuttering when it's getting to be too high and it usually will just crash or BSOD/GSOD when over the limit. For core, it's not always going to artifact. Artifacting is often due to not enough voltage so it's unstable, but sometimes the voltage is ok it's just the core can't handle that clock speed.