Sapphire 4870 overclocking

[error8]

So, I'm using the stock cooler with the fan speed modified getting only 56 C under load. My best oc is 830 mhz core/ 3800 mhz memory. I had the memory at 3900 mhz stable, but for some reason is not stable anymore ( probably because of a higher room temp ).

So , what are you getting with this card? I find it a bit strange that I can't hit 4 ghz on the GDDR since in every review I've read, 4870 can overclock quite high on the memory.

 

[F1shF4t]

I was under the impression that all 4870 cards came with ram rated at 4ghz they just undercloked them. So I tried to set that on my new MSI 4870 1gig card and was greated with a ton of artifacts. Then there is also the palit card which has its ram set at 4ghz without any heatsinks and runs perfectly stable. I'll try it out on my HIS 512 mb one to see what happens.

Don't all 512 cards use the same memory chips? I know the 1gig cards use hynix, are they rated at lower speed? Would be interesting to see what others are getting.

 

[Sylvanas]

Originally posted by: Dark Cupcake
I was under the impression that all 4870 cards came with ram rated at 4ghz they just undercloked them. So I tried to set that on my new MSI 4870 1gig card and was greated with a ton of artifacts. Then there is also the palit card which has its ram set at 4ghz without any heatsinks and runs perfectly stable. I'll try it out on my HIS 512 mb one to see what happens.

Don't all 512 cards use the same memory chips? I know the 1gig cards use hynix, are they rated at lower speed? Would be interesting to see what others are getting.

They run different mem chips, there's Hynix, Qimonda and I think the X2's use Samsung. Bottom line is there is variation and as always an OC is NEVER guaranteed, it is an added bonus. As for your particular situation, I have found that every time I have added aftermarket Mem sinks I have achieved a higher mem OC, of course to do this you will probably need an aftermarket cooling solution.

 

[F1shF4t]

Qimonda should be rated at 4ghz. Since they don't provide any other speeds in their product catalogue (well unless they doing a deal outside of that for lower speed bins)

error8 you could check what chips your card is using. It could also be the mem voltage, tighter timings etc. which cause them to overclock less.

 

[error8]

When I didn't changed the fan speed, I couldn't overclock the ram not even 100 mhz. After I did, I get it 3.8 sometimes 3.9 ghz. I still think that it might have something to do with the temperature. Anyway, if I see that you also can't touch 4 ghz I feel much better now.

 

[apoppin]

i got a very nice OC on my Sapphire 4870/512MB .. i got it the week of launch

1100Mhz on the ram and 800 on the core with the stock cooler running pretty fast - that was the max CCC allowed back when i first tested it
- later with another utility i got her to 820/1165[x4]; i didn't keep it there for very long - except to test stability - it really doesn't make that much difference in the overall performance and i hate to have it either running so hot or so loud.

edit: i looked at my notes .. yes, it did hit 820/1165 stable

 

[error8]

Originally posted by: apoppin


edit: i looked at my notes .. yes, it did hit 820/1165 stable

Stable like ATI tool stable, or like benchmarks stable. I'm asking this because many people test their overclock settings only with 3dmark or some games. If they don't see anything wrong then they assume that the card is totally stable. And some times, Vram can be 100% stable in Unreal tournament but fails in just a couple of minutes of ATI tool artifact test.

 

[F1shF4t]

I got to test my HIS 4870 512mb stock card and it is running at memclock of 1025 (4100) (and thats at 86C without the fan tweak)
Tested it with the ati tool artifact scanner.

Sapphire probably used different mem chips on your card, as I don't see any reason why a 512mb card using Qimonda GDDR5 memory chips would not be able to operate at 4ghz. As I mentioned before the palit card does it without any heatsinks on the memory so heat should not be an issue. Meh it shouldn't make much performance difference anyways.

 

[error8]

Originally posted by: Dark Cupcake
I got to test my HIS 4870 512mb stock card and it is running at memclock of 1025 (4100) (and thats at 86C without the fan tweak)
Tested it with the ati tool artifact scanner.

Sapphire probably used different mem chips on your card, as I don't see any reason why a 512mb card using Qimonda GDDR5 memory chips would not be able to operate at 4ghz. As I mentioned before the palit card does it without any heatsinks on the memory so heat should not be an issue. Meh it shouldn't make much performance difference anyways.

Noticed that you have two similar systems, one has the 512 mb variant of 4870 and the other one has the 1024 mb variant. So, are you seeing much of a difference between them? I am inclined to get the 1 gb card when it reaches the store I've bought this one from and do a little upgrade since it won't cost me too much.

 

[Ares202]

i can get 820/1050 stable but the memory gets too hot so i took it down to 1000

 

[F1shF4t]

Originally posted by: error8

Originally posted by: Dark Cupcake
I got to test my HIS 4870 512mb stock card and it is running at memclock of 1025 (4100) (and thats at 86C without the fan tweak)
Tested it with the ati tool artifact scanner.

Sapphire probably used different mem chips on your card, as I don't see any reason why a 512mb card using Qimonda GDDR5 memory chips would not be able to operate at 4ghz. As I mentioned before the palit card does it without any heatsinks on the memory so heat should not be an issue. Meh it shouldn't make much performance difference anyways.

Noticed that you have two similar systems, one has the 512 mb variant of 4870 and the other one has the 1024 mb variant. So, are you seeing much of a difference between them? I am inclined to get the 1 gb card when it reaches the store I've bought this one from and do a little upgrade since it won't cost me too much.

I haven't done any real testing between those two cards (I've had the 1gig version only for a few days)

But so far I've noticed that Mass Effect runs a LOT smoother with the 1gig version than the 512 (or even 512 crossfire for that matter, not to mention the visual anomalies you see with crossfire and the heat/power use)

I was in the same boat before. I bought two 512 cards, I wanted to see how crossfire performed. Since I found a buyer for my old 8800gtx in second comp I decided to get rid of crossfire (and eat the cost of one 512 card) and get the 1gig version, so far I don't regret the decision. The 1 gig version has an oc bios, so now I have to slow the fan for idle operation not speed it up . I just made an Idle low clocks profile which works nicely and good for older games anyways.

 

[apoppin]

Originally posted by: error8

Originally posted by: apoppin


edit: i looked at my notes .. yes, it did hit 820/1165 stable

Stable like ATI tool stable, or like benchmarks stable. I'm asking this because many people test their overclock settings only with 3dmark or some games. If they don't see anything wrong then they assume that the card is totally stable. And some times, Vram can be 100% stable in Unreal tournament but fails in just a couple of minutes of ATI tool artifact test.

stable like "game playing" stable

hours of benchmarking games

*however* it ran so hot to the touch, i couldn't take it

 

[error8]

Originally posted by: apoppin


*however* it ran so hot to the touch, i couldn't take it

So you went out and bought a 4870X2 because of that.

 

[apoppin]

Originally posted by: error8

Originally posted by: apoppin


*however* it ran so hot to the touch, i couldn't take it

So you went out and bought a 4870X2 because of that.

Yep .. but first i returned it to stock speeds .. and then i bought a 280GTX to compare with it
.. the 4870 is too slow for me

. . . and getting the X2 was like jumping from the fire pan into the fire
:sun:

the X2 cooks the inside of my case - the card itself gets hot as heck

 

[MrK6]

OP, you can probably crank the RAM a lot more. The instability is most likely from the core rather than the RAM. What I've noticed with my 4870 is overclocking the RAM puts out a tremendous amount of heat which makes it more difficult to overclock the core. Try leaving your core at 800 or 775MHz and you can probably take the RAM higher. Still, these cards seem to be core limited anyway, so I keep my RAM low to clock my core higher.

 

[error8]

Originally posted by: MrK6
OP, you can probably crank the RAM a lot more. The instability is most likely from the core rather than the RAM. What I've noticed with my 4870 is overclocking the RAM puts out a tremendous amount of heat which makes it more difficult to overclock the core. Try leaving your core at 800 or 775MHz and you can probably take the RAM higher. Still, these cards seem to be core limited anyway, so I keep my RAM low to clock my core higher.

Tested your theory, but I still can't reach a higher ram OC even with the core at stock. Anyway, I've settled with 830 / 965 X 4.

I'm very tempted to install my Accelero S1 on the card. I must resist though, since I don't want all that heat inside my case.