PSA: Malta 7990s are NOT suitable for mining!

[Spendulus]

I tried to educate you and this is what I get in return. So I see you not only need classes on thermodynamics but reading comprehension as well.

Masters in Engineering, thanks. How about you? Nope, didn't think so.

If a device consumes 500w and only generates 375w of heat, it means it's using that 125w to do what it's supposed to do and the rest (375w) is wasted in heat.

This is priceless. I'm actually going to put this quote up on my wall.

A part of the wattage is converted into accelerating air from a standstill to design speed for cooling purposes.  I suspect this becomes quite substantial. 

Consider the case of a fan alone.  It generates some heat (minor) and useful work (Major).

I'd say both you guys had the amps in --> heat/work wrong.

LOL

And where does the kinetic energy from the fan go? That's right, to heat. As soon as the air stops moving, its converted all its KE to more heat energy.

But no, a fan is not the same as a GPU.

By that logic there is no "work", only "heat".  And that's simply not true.  The useful work performed here is in moving heat from one place to another through convection.  This is not complicated.

Next we'll be arguing that there's no useful work in the entire universe, only heat....

[computerparts]

I'm going to mine with 3 of them. OP has no clue what he's talking about.

xD PLEASE do, we will enjoy the spectacle of you trying to exhaust 1200W of heat from a case while getting 500MH a card due to throttling. Please post updates.

Self belief is only a positive attribute up to a point, at which it becomes a blinding detriment.

I never said I was going to stuff them in a case. But there is a case I can think of that has proven to handle that task so I'll glady take your challenge. Care to put some btc on it as well while we're at it?

No, because you're the only one who can verify the results and I don't trust you one bit. And oh look, you have a vested interest in one of the outcomes.

Lol in other words you have ZERO confidence in your claims. Put up or shut up.

[computerparts]

So the short version of this is:

The 7990 can mine no problems, but can't run Furmark.

Good thread, OP.   

Yes and no.

The 7990 from third parties [ie the 3 slot 525W version] CAN mine no problems as long as you have 1+ gap in-between.
The official 'Malta' 7990 in 2 slot and 375W CAN'T mine - too many heat and power limitations.

I use those third party 3-slot 7990s for mining, and they do very well. I haven't tested Malta yet, but I can assume it will have issues mining. If you own a non-Malta 7990 just feel the thermals, you'll get trouble if that gets shrinked to 2 slots and to only 2 power connectors.

Furmark throttling is nothing in comparison to what scrypt mining or OC'd sha256 will do to the card. My mining temps and power draw is bigger in mining than in Furmark.

The Malta would certainly have trouble IF it used the exact same chips used in the Powercolor version. But the Malta uses higher binned chips that are more efficient which is why they can give the Malta a 375w TDP

[waterboyserver]

Not taking sides on the discussion in this thread. If power and heat seems to be a problem with Malta, it would be interesting to have it liquid cooled - though EK is releasing a block, has anyone used Arctic Accelero Hybrid coolers for mining (despite its price)?  It stands to reason the pump/block section would fit well, and the tubing might be able to pass through the grills on the top of the Malta card. The 7970 version of the Arctic cooler is expensive, using an EK 79xx shim with the regular Arctic hybrid might work interestingly - almost cooled like the Ares II but two separate loops.

[BBQKorv]

So the short version of this is:

The 7990 can mine no problems, but can't run Furmark.

Good thread, OP.  

Yes and no.

The 7990 from third parties [ie the 3 slot 525W version] CAN mine no problems as long as you have 1+ gap in-between.
The official 'Malta' 7990 in 2 slot and 375W CAN'T mine - too many heat and power limitations.

I use those third party 3-slot 7990s for mining, and they do very well. I haven't tested Malta yet, but I can assume it will have issues mining. If you own a non-Malta 7990 just feel the thermals, you'll get trouble if that gets shrinked to 2 slots and to only 2 power connectors.

Furmark throttling is nothing in comparison to what scrypt mining or OC'd sha256 will do to the card. My mining temps and power draw is bigger in mining than in Furmark.

The Malta would certainly have trouble IF it used the exact same chips used in the Powercolor version. But the Malta uses higher binned chips that are more efficient which is why they can give the Malta a 375w TDP

If Malta does have even higher binned chips than those 3-slot models, then it will be a better product than the current 7990 offerings. I'm looking forward to see where this goes when we have the first mining benchmarks of Malta. I hope I was wrong in expecting Malta to have similar chips than current 3-slot models do have. When this is cleared, most likely I'll just get more of the better model, whichever it ends up being.

Density and power consumption are better than in 7970, and that counts for me.

[rograz]

Density and power consumption are better than in 7970, and that counts for me.

Good luck running 4 or more of these in 1 rig, power consumption is only better if you don't touch the vcore of the 7970s. In general the dual cards pull 5-10W extra due the bridge chip etc and if all other parameters are identical (vcore/clocks etc) in general 2x single cards will be cooler and pulls less power than a dual card. Also add the fact that the leakage increases quite a bit with the 7xxx architecture at higher temps and it becomes even worse.

Most of the time they cost more than 2x of a single card so tell me again why someone should buy these for mining

Back when people started mining large scale with GPUs back in 2011 it was a lot hard to find decently priced motherboards with 6x PCIe slots, that was one of the main reasons 5970 became so popular for mining. Also the usage and availability of extension cables was more limited back then. There was also the whole issue about the shorting the detection pins for 1x cables that wasn't really public knowledge until mid/late 2011. These days on the other hand you can find boards for less than 100 bucks with 6 slots and higher density than 6x7970/board is just completely pointless.

[dogie]

The Malta would certainly have trouble IF it used the exact same chips used in the Powercolor version. But the Malta uses higher binned chips that are more efficient which is why they can give the Malta a 375w TDP

Looking at the data, I don't believe they are. Stock clocks less than 1GHz chips, max overclocks seem similar to my PC boards and less than decent 7970s. Power consumption was 15W less than the PC, no where near enough to make up for the lack of power headroom.

Not taking sides on the discussion in this thread. If power and heat seems to be a problem with Malta, it would be interesting to have it liquid cooled - though EK is releasing a block, has anyone used Arctic Accelero Hybrid coolers for mining (despite its price)?  It stands to reason the pump/block section would fit well, and the tubing might be able to pass through the grills on the top of the Malta card. The 7970 version of the Arctic cooler is expensive, using an EK 79xx shim with the regular Arctic hybrid might work interestingly - almost cooled like the Ares II but two separate loops.

Did you mean 7990? But anyway, this WOULDN'T work.
Max. Cooling Capacity    320 Watts. You'll max out the cooler very quickly using 375W to 525W [disputed], then just start rocketing temps until it thermal throttle crashes. This gets away with cooling a Titan because its very close to actual max power consumption and it typically assumes you're not going to mine 24/7.

It also wouldn't fix the max power draw being an issue.

Density and power consumption are better than in 7970, and that counts for me.

Good luck running 4 or more of these in 1 rig, power consumption is only better if you don't touch the vcore of the 7970s. In general the dual cards pull 5-10W extra due the bridge chip etc and if all other parameters are identical (vcore/clocks etc) in general 2x single cards will be cooler and pulls less power than a dual card. Also add the fact that the leakage increases quite a bit with the 7xxx architecture at higher temps and it becomes even worse.

Most of the time they cost more than 2x of a single card so tell me again why someone should buy these for mining

Back when people started mining large scale with GPUs back in 2011 it was a lot hard to find decently priced motherboards with 6x PCIe slots, that was one of the main reasons 5970 became so popular for mining. Also the usage and availability of extension cables was more limited back then. There was also the whole issue about the shorting the detection pins for 1x cables that wasn't really public knowledge until mid/late 2011. These days on the other hand you can find boards for less than 100 bucks with 6 slots and higher density than 6x7970/board is just completely pointless.

Exactly, no way you'd be able to run 4, or there be much point. If you're running in a case, congratulations it alone with your $4k of cards is now on fire. If running out of a case, why did you buy such high density?

The ONLY case where it makes sense, is what I used it for. I wanted a mining rig, but I only have the space to store one reasonable case.

[rograz]

Maybe for rack mounting 3x7990 rigs, maybe. That would be the only reason I can think of getting them, and that's me grasping for straws.

[dogie]

By that logic there is no "work", only "heat".  And that's simply not true.  The useful work performed here is in moving heat from one place to another through convection.  This is not complicated.

Next we'll be arguing that there's no useful work in the entire universe, only heat....

In the use of a fan, electrical energy is converted to work which is very quickly and consistently turned to heat. Why do you think a fan makes a room hotter? Because it is converted electricity to heat. -anyway, this is fans.

In electronics there is zero work as the cycle happens so fast. Apart from the tiny portion of energy required to 'start' the cycle, all the conversion is from electricity to heat.

[dogie]

I'm going to mine with 3 of them. OP has no clue what he's talking about.

xD PLEASE do, we will enjoy the spectacle of you trying to exhaust 1200W of heat from a case while getting 500MH a card due to throttling. Please post updates.

Self belief is only a positive attribute up to a point, at which it becomes a blinding detriment.

I never said I was going to stuff them in a case. But there is a case I can think of that has proven to handle that task so I'll glady take your challenge. Care to put some btc on it as well while we're at it?

No, because you're the only one who can verify the results and I don't trust you one bit. And oh look, you have a vested interest in one of the outcomes.

Lol in other words you have ZERO confidence in your claims. Put up or shut up.

No, its like me offering you a bet as to how many cups I have on my desk right now. Regardless of the true answer, I can easily fake it and there is no way to prove otherwise. I'd have to be well, you, to accept that bet.

[computerparts]

The Malta would certainly have trouble IF it used the exact same chips used in the Powercolor version. But the Malta uses higher binned chips that are more efficient which is why they can give the Malta a 375w TDP

Looking at the data, I don't believe they are. Stock clocks less than 1GHz chips, max overclocks seem similar to my PC boards and less than decent 7970s. Power consumption was 15W less than the PC, no where near enough to make up for the lack of power headroom.

I'm not sure how you missed this in the Anand review you were touting so much about

But perhaps the most defining aspect of AMD’s 7990, and the thing that sets it apart from unofficial 7990s that came before it is the TDP. AMD’s 7990 has an official TDP of just 375W, which although common for official dual-GPU cards, is quite a bit lower than the TDPs of the unofficial 7990s. As the GPU manufacturer AMD has the ability to do finely grained binning that their partners cannot, so while Asus and PowerColor have essentially been putting together cards that really are two 7970s on a single card – right down to the TDP – official 7990s get the advantage of AMD’s binning process, significantly reducing power consumption.

Third paragraph below the spec comparison table http://www.anandtech.com/show/6915/amd-radeon-hd-7990-review-7990-gets-official

No, its like me offering you a bet as to how many cups I have on my desk right now. Regardless of the true answer, I can easily fake it and there is no way to prove otherwise. I'd have to be well, you, to accept that bet.

I'm not sure how I could possibly fake pictures of the setup and cgminer running. I'm sure it can be done but it is certainly beyond my ability to do so.

[dogie]

The Malta would certainly have trouble IF it used the exact same chips used in the Powercolor version. But the Malta uses higher binned chips that are more efficient which is why they can give the Malta a 375w TDP

Looking at the data, I don't believe they are. Stock clocks less than 1GHz chips, max overclocks seem similar to my PC boards and less than decent 7970s. Power consumption was 15W less than the PC, no where near enough to make up for the lack of power headroom.

I'm not sure how you missed this in the Anand review you were touting so much about

But perhaps the most defining aspect of AMD’s 7990, and the thing that sets it apart from unofficial 7990s that came before it is the TDP. AMD’s 7990 has an official TDP of just 375W, which although common for official dual-GPU cards, is quite a bit lower than the TDPs of the unofficial 7990s. As the GPU manufacturer AMD has the ability to do finely grained binning that their partners cannot, so while Asus and PowerColor have essentially been putting together cards that really are two 7970s on a single card – right down to the TDP – official 7990s get the advantage of AMD’s binning process, significantly reducing power consumption.

Third paragraph below the spec comparison table http://www.anandtech.com/show/6915/amd-radeon-hd-7990-review-7990-gets-official

No, its like me offering you a bet as to how many cups I have on my desk right now. Regardless of the true answer, I can easily fake it and there is no way to prove otherwise. I'd have to be well, you, to accept that bet.

I'm not sure how I could possibly fake pictures of the setup and cgminer running. I'm sure it can be done but it is certainly beyond my ability to do so.

I've read that, looking at specs tells us nothing other than one heat system can remove 375W and one 525W - that's not an indication of actual performance. If you look at the actual power consumption in Anand's review you'll see the cards aren't more than 15W apart.

The 'bet' is surrounding cooling and power solutions. How am I to know if you put it next to a 5C AC and go "oh look not overheating". No I don't and I don't trust you enough to even believe your name.

[computerparts]

The Malta would certainly have trouble IF it used the exact same chips used in the Powercolor version. But the Malta uses higher binned chips that are more efficient which is why they can give the Malta a 375w TDP

Looking at the data, I don't believe they are. Stock clocks less than 1GHz chips, max overclocks seem similar to my PC boards and less than decent 7970s. Power consumption was 15W less than the PC, no where near enough to make up for the lack of power headroom.

I'm not sure how you missed this in the Anand review you were touting so much about

But perhaps the most defining aspect of AMD’s 7990, and the thing that sets it apart from unofficial 7990s that came before it is the TDP. AMD’s 7990 has an official TDP of just 375W, which although common for official dual-GPU cards, is quite a bit lower than the TDPs of the unofficial 7990s. As the GPU manufacturer AMD has the ability to do finely grained binning that their partners cannot, so while Asus and PowerColor have essentially been putting together cards that really are two 7970s on a single card – right down to the TDP – official 7990s get the advantage of AMD’s binning process, significantly reducing power consumption.

Third paragraph below the spec comparison table http://www.anandtech.com/show/6915/amd-radeon-hd-7990-review-7990-gets-official

No, its like me offering you a bet as to how many cups I have on my desk right now. Regardless of the true answer, I can easily fake it and there is no way to prove otherwise. I'd have to be well, you, to accept that bet.

I'm not sure how I could possibly fake pictures of the setup and cgminer running. I'm sure it can be done but it is certainly beyond my ability to do so.

I've read that, looking at specs tells us nothing other than one heat system can remove 375W and one 525W - that's not an indication of actual performance. If you look at the actual power consumption in Anand's review you'll see the cards aren't more than 15W apart.

The 'bet' is surrounding cooling and power solutions. How am I to know if you put it next to a 5C AC and go "oh look not overheating". No I don't and I don't trust you enough to even believe your name.

Now you bring in ambient temps ha! You're full of excuses aren't you? I'll leave it at that.

[dogie]

The Malta would certainly have trouble IF it used the exact same chips used in the Powercolor version. But the Malta uses higher binned chips that are more efficient which is why they can give the Malta a 375w TDP

Looking at the data, I don't believe they are. Stock clocks less than 1GHz chips, max overclocks seem similar to my PC boards and less than decent 7970s. Power consumption was 15W less than the PC, no where near enough to make up for the lack of power headroom.

I'm not sure how you missed this in the Anand review you were touting so much about

But perhaps the most defining aspect of AMD’s 7990, and the thing that sets it apart from unofficial 7990s that came before it is the TDP. AMD’s 7990 has an official TDP of just 375W, which although common for official dual-GPU cards, is quite a bit lower than the TDPs of the unofficial 7990s. As the GPU manufacturer AMD has the ability to do finely grained binning that their partners cannot, so while Asus and PowerColor have essentially been putting together cards that really are two 7970s on a single card – right down to the TDP – official 7990s get the advantage of AMD’s binning process, significantly reducing power consumption.

Third paragraph below the spec comparison table http://www.anandtech.com/show/6915/amd-radeon-hd-7990-review-7990-gets-official

No, its like me offering you a bet as to how many cups I have on my desk right now. Regardless of the true answer, I can easily fake it and there is no way to prove otherwise. I'd have to be well, you, to accept that bet.

I'm not sure how I could possibly fake pictures of the setup and cgminer running. I'm sure it can be done but it is certainly beyond my ability to do so.

I've read that, looking at specs tells us nothing other than one heat system can remove 375W and one 525W - that's not an indication of actual performance. If you look at the actual power consumption in Anand's review you'll see the cards aren't more than 15W apart.

The 'bet' is surrounding cooling and power solutions. How am I to know if you put it next to a 5C AC and go "oh look not overheating". No I don't and I don't trust you enough to even believe your name.

Now you bring in ambient temps ha! You're full of excuses aren't you? I'll leave it at that.

.... Yes? As already discussed ambient is going to affect power usage and actual TDP of the cooling? Really, this is why you're what, 35, and still running a piddly little computer store trying to sell usb cables to diddy old grannies.

[FloridaBear]

Next we'll be arguing that there's no useful work in the entire universe, only heat....

Correct, ultimately.

[Dyaheon]

With regards to power throttling, there's a powertune +20% option. I believe that should let you mine without trouble, as it allows for 375W*1.2 = 450W. Furmark is indeed not a good benchmark, it is considered a 'power virus'. Even if power is a problem, slight undervolting should take care of that.

Temperatures and cooling may be a problem, but it's a matter of ambient temps and airflow. If you have an open air rig with extenders and plenty of space for the cards, I'm sure you'll be fine.

The question is more about whether it's a good idea to buy a $1000 card for mining now, instead of getting multiple 5xxx/79xx cards or an ASIC. Or just buying coins directly. The time of GPUs might be coming to an end.

[dogie]

With regards to power throttling, there's a powertune +20% option. I believe that should let you mine without trouble, as it allows for 375W*1.2 = 450W. Furmark is indeed not a good benchmark, it is considered a 'power virus'. Even if power is a problem, slight undervolting should take care of that.

Temperatures and cooling may be a problem, but it's a matter of ambient temps and airflow. If you have an open air rig with extenders and plenty of space for the cards, I'm sure you'll be fine.

The question is more about whether it's a good idea to buy a $1000 card for mining now, instead of getting multiple 5xxx/79xx cards or an ASIC. Or just buying coins directly. The time of GPUs might be coming to an end.

The limit is the cooling system and power DELIVERY in this case [same as you'd have on a high end SINGLE 7970 with a little more beef]. It doesn't matter if you tell the card its allowed more than designed as in this case its hard limited by the power delivery system. 75W PCIE and 2x150W PCIE 8 pins = 375W. Can't 'force' more due to the onboard hardware without seriously seriously risking card death.

[computerparts]

With regards to power throttling, there's a powertune +20% option. I believe that should let you mine without trouble, as it allows for 375W*1.2 = 450W. Furmark is indeed not a good benchmark, it is considered a 'power virus'. Even if power is a problem, slight undervolting should take care of that.

Temperatures and cooling may be a problem, but it's a matter of ambient temps and airflow. If you have an open air rig with extenders and plenty of space for the cards, I'm sure you'll be fine.

The question is more about whether it's a good idea to buy a $1000 card for mining now, instead of getting multiple 5xxx/79xx cards or an ASIC. Or just buying coins directly. The time of GPUs might be coming to an end.

The limit is the cooling system and power DELIVERY in this case [same as you'd have on a high end SINGLE 7970 with a little more beef]. It doesn't matter if you tell the card its allowed more than designed as in this case its hard limited by the power delivery system. 75W PCIE and 2x150W PCIE 8 pins = 375W. Can't 'force' more due to the onboard hardware without seriously seriously risking card death.

...

[dogie]

With regards to power throttling, there's a powertune +20% option. I believe that should let you mine without trouble, as it allows for 375W*1.2 = 450W. Furmark is indeed not a good benchmark, it is considered a 'power virus'. Even if power is a problem, slight undervolting should take care of that.

Temperatures and cooling may be a problem, but it's a matter of ambient temps and airflow. If you have an open air rig with extenders and plenty of space for the cards, I'm sure you'll be fine.

The question is more about whether it's a good idea to buy a $1000 card for mining now, instead of getting multiple 5xxx/79xx cards or an ASIC. Or just buying coins directly. The time of GPUs might be coming to an end.

The limit is the cooling system and power DELIVERY in this case [same as you'd have on a high end SINGLE 7970 with a little more beef]. It doesn't matter if you tell the card its allowed more than designed as in this case its hard limited by the power delivery system. 75W PCIE and 2x150W PCIE 8 pins = 375W. Can't 'force' more due to the onboard hardware without seriously seriously risking card death.

...

Still not caught on that power consumption is equal or very near to heat output?

[computerparts]

With regards to power throttling, there's a powertune +20% option. I believe that should let you mine without trouble, as it allows for 375W*1.2 = 450W. Furmark is indeed not a good benchmark, it is considered a 'power virus'. Even if power is a problem, slight undervolting should take care of that.

Temperatures and cooling may be a problem, but it's a matter of ambient temps and airflow. If you have an open air rig with extenders and plenty of space for the cards, I'm sure you'll be fine.

The question is more about whether it's a good idea to buy a $1000 card for mining now, instead of getting multiple 5xxx/79xx cards or an ASIC. Or just buying coins directly. The time of GPUs might be coming to an end.

The limit is the cooling system and power DELIVERY in this case [same as you'd have on a high end SINGLE 7970 with a little more beef]. It doesn't matter if you tell the card its allowed more than designed as in this case its hard limited by the power delivery system. 75W PCIE and 2x150W PCIE 8 pins = 375W. Can't 'force' more due to the onboard hardware without seriously seriously risking card death.

...

Still not caught on that power consumption is equal or very near to heat output?

Pci-e 2.0 is capable of delivering 150w not 75. About the power consumption yes you're right. I was thinking of something entirely different. Are you sitting there constantly refreshing the screen? I cannot fathom how you can reply so fast unless you have nothing better to do.