[GuineaMcPig]

Alright, I know there are a number of obvious answers to this question (like "when there's smoke spewing out of your computer") but I'd like some opinions all the same.

I recently posted a thread about upgrading the graphics card in my G5 mac. After a number of helpful responses I decided on the X800 XT and installed it yesterday. The improvement was immediately noticeable.

I've already used a program called ATIccelerator II to overclock the core and memory speeds from 475 mhz to 500 mhz. I was able to squeeze out a few fps in World of Warcraft which is nice (I'm running all settings max except for Terrain draw distance which is about 50%).

Now, I realize this may be a dangerous question to ask with a $375 piece of hardware, but how much more can I safely get out of this puppy? I've turned to http://www.barefeats.com/radx800.html for reasonable suggestions, and one thing confused me. On the overclocked X800 XT that he used for performance tests, he lists the "effective memory clock speed" at 1100 mhz. That's more than twice what my card is running at. The word "effective" makes me a little confused, so I figured I'd wait to here from someone who knows what they're talking about before I increase the memory clock speed by more than double its current number.

So, is there any common wisdom about how much you can reliably overclock a graphics card? Or is it totally dependent on the model?

Thanks again for the help!

~Jordan

 

[Cyrillic]

Bump it up a very small amount at a time (like 10 mhz). If you see artifacts, you've gone too far. If games start crashing unexpectedly, you've gone too far. If any sort of explosion happens, you've gone too far.

I take no liability. What I said may be suicide for your computer. Good luck!

 

[gshan]

Only if you can afford to lose the card, and just make sure you have GOOD cooling.

 

[no1likesme]

you may want to up your agp or pci-e voltage because as long as you have good cooling it will prevent some artifacts

also go to amdforums.com they will be able to help a lot more than here

 

[imported_Echo_]

Quote:

Originally Posted by GuineaMcPig Alright, I know there are a number of obvious answers to this question (like "when there's smoke spewing out of your computer") but I'd like some opinions all the same. I recently posted a thread about upgrading the graphics card in my G5 mac. After a number of helpful responses I decided on the X800 XT and installed it yesterday. The improvement was immediately noticeable. I've already used a program called ATIccelerator II to overclock the core and memory speeds from 475 mhz to 500 mhz. I was able to squeeze out a few fps in World of Warcraft which is nice (I'm running all settings max except for Terrain draw distance which is about 50%). Now, I realize this may be a dangerous question to ask with a $375 piece of hardware, but how much more can I safely get out of this puppy? I've turned to http://www.barefeats.com/radx800.html for reasonable suggestions, and one thing confused me. On the overclocked X800 XT that he used for performance tests, he lists the "effective memory clock speed" at 1100 mhz. That's more than twice what my card is running at. The word "effective" makes me a little confused, so I figured I'd wait to here from someone who knows what they're talking about before I increase the memory clock speed by more than double its current number. So, is there any common wisdom about how much you can reliably overclock a graphics card? Or is it totally dependent on the model? Thanks again for the help! ~Jordan

there is a core clock and a memory clock your core clock is 475 and memory clock is most likely 1000 stock

 

[Jbucla2005]

basically, you want to avoid crashes and instability issues, also artifacts... once you start getting artifacts, you've gone too far

 

[roastpuff]

There's an ATI overclocking utility that will do it for you... I believe it's ATItool?

It'll find the maximum speeds of your GPU and memory for you, stress them at that speed and test for artifacts. Utterly automated, and easy to use.

Of course, running some 3DMark05 tests to back up ATItool's stability results doesn't hurt any.

 

[GuineaMcPig]

Let me ammend what I said earlier...first of all, I'm using a program called ATIccelerator II which lists the core and memory frequencies. I have the core overclocked by about 6% and have kept the memory stock (it's listed at 500 mhz). According to sites like BareFeats (which I linked in my previous post), the X800 XT "effective" memory speed can be reliably clocked to 1100 mhz. So I'm guessing what this means is that I can bump it up from 500 mhz to 550 without too much problems?

I don't know what "effective" memory speed means but I'm suspicious that a factor of 2 is involved somewhere (either "effective" means double the stated memory frequency, or ATIccelerator is listing my own card's frequency at half of what it actually is).

EDIT: ATitool looks incredibly useful, but it appears to be PC only

 

[Shakey]

Quote:

On the overclocked X800 XT that he used for performance tests, he lists the "effective memory clock speed" at 1100 mhz. That's more than twice what my card is running at. The word "effective" makes me a little confused, so I figured I'd wait to here from someone who knows what they're talking about before I increase the memory clock speed by more than double its current number.

Effective memory clock speed is just referring to the DDR dual memory channel, where data is sent over the bus at twice the speed of the clock. A 500MHz bus behaves like a1000MHz one would and the memory used on this bus is known by the higher speed.

 

[Shakey]

double post

 

[GuineaMcPig]

Quote:

Originally Posted by Shakey Effective memory clock speed is just referring to the DDR dual memory channel, where data is sent over the bus at twice the speed of the clock. A 500MHz bus behaves like a1000MHz one would and the memory used on this bus is known by the higher speed.

Awesome...thanks for the explanation there. It seems like I could bump up the memory clock speed from 500 to 550 mhz without much of a problem, according to Barefeats anyway. I think I'll stick with that info instead pushing it further (I don't have any aftermarket cooling so changing the voltage is not something I could safely do).

 

[Shakey]

Even without increasing voltage, upping the clock speed will generate more heat and heat kills! Just be careful about cooling. OTOH, I don't think that there have been all that many cards killed by overclocking. I mean, some cards do get killed in the line of OC'ing duty, but by and large, you system will prob. just freeze up and you'll have to re-boot at a lower speed.

 

[Xert]

With an ATI X800XT or X50XT, there's no problem overclocking them to Platinum Edition levels, since the PEs are just factory overclocked XTs anyway. As an owner of an X850XT, I've never had a problem.

 

[jpr703]

Unless you're overclocking for a specific reason (ie. trying to get a new game to run at a playable framerate) you're probably better off leaving it alone. No sense risking your entire investment over a few frames per second that you might not even be able to notice during the course of normal gameplay.

 

[xSolsticex]

Here is my take on this:

1) Stay away from upping the voltage. More volts requires mods and you wont get much more from the increase in voltage unless you are useing water or extreme cooling.

2) Go slowly. Up the MHz a bit at a time and make sure that it is stable before proceeding

3) Consider upgrading the cooling. The x800XT isnt the hottest card on the market, but overclocking will increase heat. Consider an upgraded heatsink, such as the Zalman VF700-Cu. I ran one of these on my old O/Ced x800XL, and it was great. I plan on getting one for my 7800GT when I get a bit more cash. This cooler is pretty easy to install, and comes with clear instructions.

4) Dont overclock if you cant afford to lose the hardware. As many have suggested in this thread, you probably be better off keeping the card at stock if you cant really afford to lose it. I guess I am being hypocrytical though, since I run a highly O/Ced rig and I cant afford to lose a single part. I guess I like risks