if the 5850 clocks to performance of the 5870

[BTRY B 529th FA BN]

I've heard the 5850 overclocks to the performance of the 5870, so my question is, how well in performance does the 5870 overclock to?

 

[toyota]

Originally posted by: BTRY B 529th FA BN
I've heard the 5850 overclocks to the performance of the 5870, so my question is, how well in performance does the 5870 overclock to?

what do you mean "you have heard". every card is different so there is no way to draw a real conclusion at this point. hell xbit got artifacts just at 30mhz over the stock core clocks on a 5870. in the firingsquad review of the 5850 they got 878 on one but only 815 on an another. in other words overclocks for both the 5850 and 5870 can be all over the place.

 

[BTRY B 529th FA BN]

Originally posted by: toyota

Originally posted by: BTRY B 529th FA BN
I've heard the 5850 overclocks to the performance of the 5870, so my question is, how well in performance does the 5870 overclock to?

what do you mean "you have heard". every card is different so there is no way to draw a real conclusion at this point. hell xbit got artifacts just at 30mhz over the stock core clocks on a 5870. in the firingsquad review of the 5850 they got 878 on one but only 815 on an another. in other words overclocks for both the 5850 and 5870 can be all over the place.

ok, so that is interesting, :thumbsup: thanks for the update

 

[thilanliyan]

The ASUS version with voltage tweaking can apparently OC to 1000MHz core.

 

[yh125d]

toyota is right, clocks are all over the place right now due to the 40nm process being fairly new still. As time goes on and the manufacturing matures there should be more stability insofar as the majority should be able to OC by XXX amount pretty regularly. Hopefully this will happen right around Christmas, maybe we'll even be lucky enough to see a 5890 part for some great OC's to coincide with the GF100 release

 

[BTRY B 529th FA BN]

where did i read the overclock was stable at max within CCC allowances?

 

[Tempered81]

http://www.techpowerup.com/reviews/HIS/HD_5850/32.html

The overclocks of our card are 835 MHz core (15% overclock) and 1260 MHz Memory (26% overclock). For your reference, the defaults are 725 / 1000 (GPU-Z is showing the wrong values due to a bug which will be fixed in the next version). As a percentage those overclocks are really nice. The maximum core clock of 835 MHz is clear evidence that this GPU ended on a HD 5850 because it could not handle the HD 5870 clock speeds of 850 MHz. The memory chips are exactly the same as on the HD 5870, which results in roughly the same maximum memory clock. In essence you can get a HD 5850 and overclock it to almost HD 5870 performance levels in just a few minutes. I would also like to point out that you can increase the voltage for better GPU overclocking. The default voltage of 1.09 V is quite low and there is plenty temperature headroom as well. So I ran a quick test at 1.30 V GPU and reached a maximum core clock of 1000 MHz.
As mentioned in the HD 5870 article, overclocking the memory on these cards is quite different from any other card so far. Normally you'd expect rendering errors or crashes, but not with these cards. Thanks to the new error correction algorithm in the memory controller, every memory error is just retransmitted until everything is fine. So once you exceed the "stable" clock frequency, memory errors will appear more often, get retransmitted, but the rendered output will still look perfectly fine. The only difference is that performance drops, the further you increase the clocks, the lower the performance gets. As a result a normal "artifact scanning" approach to memory overclocking on the HD 5800 Series will not work. You have to manually increase the clocks and observe the framerate until you find the point where performance drops.

http://www.xtremesystems.org/f...howthread.php?t=235693

 

[Yukmouth]

ATI cards have never really scaled that well out of spec and getting big brother performance out of a value card would be a complete shot in the dark.

With AMD in the mix, you can be sure defective cores, or, less capeable cores are finding their way to the 5850's. Kinna like my POS Phenom II X3 that consistantly takes more voltage to reach higher clock speeds than its four processor counterpart.

 

[bunnyfubbles]

The GPUs are going to be really similar in how high they can go. The ASUS boards that allow overvolting are interesting because ASUS claims the 5850 will actually hit 1050MHz whereas the 5870 tops out at 1035, of which I could only assume this has to do with the GPU being whole and harder to hit the higher speed (of which the 15MHz difference is very negligible, but still).

But that aside, the big difference is going to be in the memory. The two cards will most likely come with the same GDDR5 modules, of which that means the 5870's GDDR5 is clocked close to its max 1200MHz vs. 1300MHz, whereas the 5850 is "underclocked" to 1000MHz vs. 1200MHz or 1300MHz. Now as GDDR5 that difference ends up being 4000MHz vs 4800MHz vs 5200MHz, so going from 4000 to 4800-5200 is a huge leap for 5850, whereas the 5870 is already kind of topped out, perhaps being able to squeeze from 4800 to 5200.

 

[BTRY B 529th FA BN]

Interesting bunnyfubbles... those kinds of points make the 5850 more appealing - we'll just have to wait for some good review sights ... *cough* Anand *cough* hehe

 

[bunnyfubbles]

Originally posted by: BTRY B 529th FA BN
Interesting bunnyfubbles... those kinds of points make the 5850 more appealing - we'll just have to wait for some good review sights ... *cough* Anand *cough* hehe

yeah, this go around is interesting because it isn't quite like the 4850 vs 4870 where the GPUs were virtually identical (outside of clock rate) however the 4850 was stuck with GDDR3 vs. the 4870's GDDR5 where it was physically impossible for memory overclocking could bring the 4850's memory anywhere near close to the bandwidth of the 4870's.

Instead, the primary difference here is the 5850's 160 fewer SPs (1440 vs. 1600) and 8 fewer TMUs (72 vs. 80), and clock rate...although that can be compensated with overclocking.

So really, a person who knew what they were doing could take a 5850 and turn it into something that is more in line with being (at worst) 90+% of what a 5870 can be, but at ~68% of the cost

 

[cbn]

Don't these HD58xx Video cards seem to suffer from *relative* lack of memory bandwidth?

If that is the case I wouldn't be suprised to see HD5850 do better than HD5870 if the memory were overclocked higher.

Nice thing about HD5870 and HD5850 is that supoosedly have the same memory chips (capable of 1.4 Ghz...or something like that)

 

[MrK6]

Originally posted by: Just learning
Don't these HD58xx Video cards seem to suffer from *relative* lack of memory bandwidth?

If that is the case I wouldn't be suprised to see HD5850 do better than HD5870 if the memory were overclocked higher.

Nice thing about HD5870 and HD5850 is that supoosedly have the same memory chips (capable of 1.4 Ghz...or something like that)

Nah, there's more than enough bandwidth for the card. For some reason, every time someone sees a card that doesn't have a 512-bit bus, everyone screams about being bandwidth starved. It's always blown way out of proportion. And the cards use 5GBps-rated chips (1.25GHz).

OP, the 5850 can clock to the same performance of a 5870, but will need higher frequency than the 5870 to match it due to its having one less shader cluster (correct term?). The 5870 clocks well given the ease of software voltage regulation. I've had mine up to 1030MHz core for benchmarking and testing, and I'm sure better cooling/better cards can go further.

 

[nyker96]

considering they are using similar DDR5 chip for both, 5850 can do 1200-1300 on DDR5s from reviews and GPU clocks to 800-850 even 900+ in some reviews. of course a few did less but 800+ looks good. also 5850 has 2x6pin providing enough power for the OC to work on this card. we have to wait for some nicer custom cooler design to show up to take advantage of this head room better. after OC this card should be very very close to stock 5870s.

 

[Tempered81]

Heres a 1440sp HD5850 @ 1000 core / 5000 mem @ 1.3v on the core and stock volts on memory:

http://tpucdn.com/reviews/HIS/...50/images/gpuz_oc2.gif

 

[lopri]

Do we have information of the followings? Stock voltages.

----------- 5870 --------- 5850
2D Idle -- ______V ---- ______V
2D Perf -- ______V ---- ______V
3D Perf -- ______V ---- ______V

And I assume 2D clock frequencies for 5850 and 5870 are same and only the 3D frequencies differ?

@MrK6: How do you like your 5870 @2560x1600? Gaming-wise, and video-wise? I read from 5870 review AMD did some tweaks to its UVD2 engine. Is it something you notice while playing back HD clips?

 

[Tempered81]

Not stated as a fact by ati anywhere, but this is what i've seen posted on various forums.

----------------- 5870 ------------ 5850
2D Idle -- ___0.945___V ---- ___0.085___V
3D Perf -- ___1.15____V ---- ___1.09___V (two people reported 1.125v & 1.162v on 5870)
OCP limit ___~1.4?___V ---- __~1.33?__V

5870 2d is 157c / 300mem with single display, with multiple it's higher like 400c and increases idle power draw from 27w to ~35-40w. I thought 5850 2d would be the same, but first gpu-z shots show 400mhz core.

 

[bunnyfubbles]

Originally posted by: Tempered81
Heres a 1440sp HD5850 @ 1000 core / 5000 mem @ 1.3v on the core and stock volts on memory:

http://tpucdn.com/reviews/HIS/...50/images/gpuz_oc2.gif

that's hot

do you know the brand and how it was overvolted? I can guess it was an HIS...

 

[Zinthar]

The 5850 looks like an amazing card for the money, and the perfect replacement for my 4870x2 -- OC it to around 900mhz on the core to match the performance of the latter (and likely exceed it once the 58xx drivers mature), minus the CF quirks, and save $80-100/yr. in power savings from the use of the former. The market price for a used 4870x2 seems to be about on par with the 5850.

 

[LCD123]

With CPUs, one can buy a $200 CPU and OC it to 80% the performance of an OCed $1000 CPU! But with GPUs, the price is much closer. No $100 GPU will ever come close to a $500 GPU! You need a $300 GPU OCed to come 90% of a $400 OCed GPU

 

[CyberAtomix]

have my asus 5870 overclocked @ 925/1250
runs fine no problems so far

 

[MrK6]

Originally posted by: lopri
Do we have information of the followings? Stock voltages.

----------- 5870 --------- 5850
2D Idle -- ______V ---- ______V
2D Perf -- ______V ---- ______V
3D Perf -- ______V ---- ______V

And I assume 2D clock frequencies for 5850 and 5870 are same and only the 3D frequencies differ?

@MrK6: How do you like your 5870 @2560x1600? Gaming-wise, and video-wise? I read from 5870 review AMD did some tweaks to its UVD2 engine. Is it something you notice while playing back HD clips?

From my BIOS read-out I get 0.95V, 1.063V, and 1.162V. So, my guess is that's your 2D idle, 2D Perf, and 3D Perf respectively. There's a total of 7 clock info modes listed in the BIOS (as opposed to 9 in the 4870). Idle is 157/300, and there's 850/1200 for full speed. There's also three other modes listed - 600/900 @ 1.063V, 400/900 @ 1.063V, and 400/1200 @ 1.063V. If I had to take a stab at guessing which they are, just based on what I know of the card and what I've read, 600/900 is throttling, 400/900 (labeled UVD) is for playback, and 400/1200 is for dual displays.

I don't actually use my computer for any high-def playback (I watch a regular DVD maybe once every two months), so I really can't comment on it's performance. Game-wise, it's amazing. The drivers still need work as I don't think the card is getting as much performance as it should be, but that'll come. I "side-stepped" over from my GTX295, and I have to say there's a marked improvement in gameplay quality, especially with "smoothness" and flow. The overclocking capabilities of such a new chip are also impressive, especially considering the ease of software voltage modification. I'm still tinkering around with voltages and capabilties, but at 950MHz, this card is insane. I imagine better samples that can get to 1000MHz 24/7 with minor voltage adjustments will quite amazing.

Originally posted by: bunnyfubbles

Originally posted by: Tempered81
Heres a 1440sp HD5850 @ 1000 core / 5000 mem @ 1.3v on the core and stock volts on memory:

http://tpucdn.com/reviews/HIS/...50/images/gpuz_oc2.gif

that's hot

do you know the brand and how it was overvolted? I can guess it was an HIS...

The MSI Afterburner program works on all brands, that'd be my guess (a big kudos to MSI).

 

[SlowSpyder]

Originally posted by: CyberAtomix
have my asus 5870 overclocked @ 925/1250
runs fine no problems so far

Now overclock that CPU.

 

[Tempered81]

Originally posted by: MrK6
From my BIOS read-out I get 0.95V, 1.063V, and 1.162V. So, my guess is that's your 2D idle, 2D Perf, and 3D Perf respectively. There's a total of 7 clock info modes listed in the BIOS (as opposed to 9 in the 4870). Idle is 157/300, and there's 850/1200 for full speed. There's also three other modes listed - 600/900 @ 1.063V, 400/900 @ 1.063V, and 400/1200 @ 1.063V. If I had to take a stab at guessing which they are, just based on what I know of the card and what I've read, 600/900 is throttling, 400/900 (labeled UVD) is for playback, and 400/1200 is for dual displays.

I don't actually use my computer for any high-def playback (I watch a regular DVD maybe once every two months), so I really can't comment on it's performance. Game-wise, it's amazing. The drivers still need work as I don't think the card is getting as much performance as it should be, but that'll come. I "side-stepped" over from my GTX295, and I have to say there's a marked improvement in gameplay quality, especially with "smoothness" and flow. The overclocking capabilities of such a new chip are also impressive, especially considering the ease of software voltage modification. I'm still tinkering around with voltages and capabilties, but at 950MHz, this card is insane. I imagine better samples that can get to 1000MHz 24/7 with minor voltage adjustments will quite amazing.

What a great post, thank you MrK6.

 

[cbn]

Originally posted by: MrK6

Originally posted by: Just learning
Don't these HD58xx Video cards seem to suffer from *relative* lack of memory bandwidth?

If that is the case I wouldn't be suprised to see HD5850 do better than HD5870 if the memory were overclocked higher.

Nice thing about HD5870 and HD5850 is that supoosedly have the same memory chips (capable of 1.4 Ghz...or something like that)

Nah, there's more than enough bandwidth for the card. For some reason, every time someone sees a card that doesn't have a 512-bit bus, everyone screams about being bandwidth starved. It's always blown way out of proportion. And the cards use 5GBps-rated chips (1.25GHz).

OP, the 5850 can clock to the same performance of a 5870, but will need higher frequency than the 5870 to match it due to its having one less shader cluster (correct term?). The 5870 clocks well given the ease of software voltage regulation. I've had mine up to 1030MHz core for benchmarking and testing, and I'm sure better cooling/better cards can go further.

I've seen one benchmark (in the form of a simple graph) where a 878 Mhz 1440 shader HD5850 actually did better than a 1600 shader @ 850 MHz HD5870......but the HD5850 had its memory @ ~1400 Mhz.

This tells me that in that testing scenario memory bandwidth was the bottleneck....not GPU power.

Let me see if I can find the graph. I am sure it was probably 2560x1600 with heavy AA/AF for that to happen though.