Bitcoin Forum

Bitcoin => Mining => Topic started by: Jered Kenna (TradeHill) on March 09, 2011, 08:48:21 PM



Title: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Jered Kenna (TradeHill) on March 09, 2011, 08:48:21 PM
Really leaning towards  used 5970 or a new 6950

The prices are similar but the 5970 is going to have higher performance (and heat / watt) correct?


Just wondering if it's still king.

Thanks in advance guys. ;D


Edit: memory size or anything else important? Basically wondering what stats makes the best miner.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: mortalis on March 09, 2011, 08:55:52 PM
The 6990 only has 3072 Stream processors compared to the 5970's 3200 stream processors. So, correct me if I'm wrong, but the 5970 is still king.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: xenon481 on March 09, 2011, 09:05:06 PM
Integer Computations Per Watt is the only significant factor. And the cost of the card itself.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Jered Kenna (TradeHill) on March 09, 2011, 09:08:13 PM
Integer Computations Per Watt is the only significant factor. And the cost of the card itself.

Thanks that's what I was looking for (thanks mortalis too, good info)

Now I have to ask: how do we determine integer computations? Straight up stream processors? Anything else to worry about like memory bandwith etc etc?


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Garrett Burgwardt on March 09, 2011, 10:03:03 PM
The 6990 only has 3072 Stream processors compared to the 5970's 3200 stream processors. So, correct me if I'm wrong, but the 5970 is still king.

False. The 6970 has fewer SPs than the 5870 but still hashes faster. I'd expect the same from the 6990


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: martok on March 09, 2011, 10:09:57 PM
It'll be interesting to see hash results on the 6990 and I'm sure that'll happen soon enough. I think a better question though and it's been discussed elsewhere is whether to build a rig at this point at all. If difficulty keeps increasing at current rates, you will be hard pressed to recover an investment into a 5970 or a 6950. You could do it today assuming difficulty stays where it is but that isn't going to happen and video cards depreciate rather quickly indeed.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Jered Kenna (TradeHill) on March 09, 2011, 10:28:34 PM
It'll be interesting to see hash results on the 6990 and I'm sure that'll happen soon enough. I think a better question though and it's been discussed elsewhere is whether to build a rig at this point at all. If difficulty keeps increasing at current rates, you will be hard pressed to recover an investment into a 5970 or a 6950. You could do it today assuming difficulty stays where it is but that isn't going to happen and video cards depreciate rather quickly indeed.


The only thing I have going for me is I live in Chile. Cards are more expensive here. I'm from the states originally so I can bring a few used cards down, put them up for sale and mine with them until they're sold. I either break even on the cards or profit a little.

I also partially want to do it from a "help the community perspective" I'm not just in it for cash. I'm looking in to electricity costs and options now, if I can find some cheap power that makes it a lot better.

It's looking like used 5970's is the way to go.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: mortalis on March 09, 2011, 10:31:59 PM
I see. What component makes it Hash faster?

The 6990 only has 3072 Stream processors compared to the 5970's 3200 stream processors. So, correct me if I'm wrong, but the 5970 is still king.

False. The 6970 has fewer SPs than the 5870 but still hashes faster. I'd expect the same from the 6990


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Grinder on March 09, 2011, 10:49:16 PM
I see. What component makes it Hash faster?
Higher clock rate.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Jered Kenna (TradeHill) on March 09, 2011, 10:59:46 PM
I see. What component makes it Hash faster?
Higher clock rate.

That's the only thing at all that matters (reasonably)? Makes the search a hell of a lot more simple if that's so.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: xenon481 on March 09, 2011, 11:07:41 PM
You can estimate the relative integer performance of an ATI card by multiplying the number of stream processors by the clock of the GPU.

But, you need to also take into account the Wattage that will be used. Hash per Watt is better than just straight up more Hashes.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Jered Kenna (TradeHill) on March 09, 2011, 11:15:20 PM
You can estimate the relative integer performance of an ATI card by multiplying the number of stream processors by the clock of the GPU.

But, you need to also take into account the Wattage that will be used. Hash per Watt is better than just straight up more Hashes.

For the most part it's better, have to figure in the other parts of the computer taking up a little power and cost of buying them.
I'd prefer a slightly less efficient GPU than building a whole other computer to double my GPU's

But yeah you're right in general. Also didn't know that about multiplying steam processors by clock speed.
Thanks.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: [Tycho] on March 10, 2011, 01:08:01 AM
The 6990 only has 3072 Stream processors compared to the 5970's 3200 stream processors. So, correct me if I'm wrong, but the 5970 is still king.
False. The 6970 has fewer SPs than the 5870 but still hashes faster. I'd expect the same from the 6990
5970 is considerably cheaper per GH/s.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Garrett Burgwardt on March 10, 2011, 02:05:32 AM
The 6990 only has 3072 Stream processors compared to the 5970's 3200 stream processors. So, correct me if I'm wrong, but the 5970 is still king.
False. The 6970 has fewer SPs than the 5870 but still hashes faster. I'd expect the same from the 6990
5970 is considerably cheaper per GH/s.

I never said it was cost effective, just that the 6990 hashes faster than the 5970.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Garrett Burgwardt on March 10, 2011, 02:52:42 AM
It seems that 5970 is still the king for mining, if you can get them.

That said, I'll be happy to sell mine after May 25th ;D


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Steve on March 10, 2011, 04:51:18 AM
It seems that 5970 is still the king for mining, if you can get them.

Is it really that hard to get them?  The local store near me has them for $599.  Although, I bought a second one the other day and they only had two left (not sure if they had more in the back).


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Syke on March 10, 2011, 06:44:23 AM
The 6990 only has 3072 Stream processors compared to the 5970's 3200 stream processors. So, correct me if I'm wrong, but the 5970 is still king.

False. The 6970 has fewer SPs than the 5870 but still hashes faster. I'd expect the same from the 6990
What makes you think that? My 5870s pull about 340 mhps, and my 6970 pulls about 320 mhps. The difference is likely attributed to the slower drivers needed to support the 6xxx series.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Jered Kenna (TradeHill) on March 10, 2011, 03:07:15 PM
What about the nvidia side of the fence?
460's are priced really well.

In general does it matter if you go nvidia or ATI?

How's the 460 fare? Can get them pretty damn cheap and they're not bad cards at all.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Garrett Burgwardt on March 10, 2011, 03:14:06 PM
Nvidia cards suck at fixed point calculations for some reason. And they're usually slower in games too ;)

Stay away from the Green team, Toronto is way better overall :)


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Jered Kenna (TradeHill) on March 10, 2011, 04:02:18 PM
I've always leaned towards red, just seemed like you get more for your money too the last few generations.
Thanks for the advice.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: dust on March 10, 2011, 09:37:33 PM
Judging from that pic, means that you need to make your own guides for it from plastic, or even make it travel out of the back and then over the case and out.
http://i.imgur.com/kIoH7.png

That doesn't look like a good idea, as the hot air would be redirected back over the intake of the fan.  Some large side exhaust fans would help cool this card ... or even better, water cooling.

I've always leaned towards red, just seemed like you get more for your money too the last few generations.
Thanks for the advice.

Before I started mining bitcoins, I preferred nvidia. (Probably due to hearing about poor ATI drivers and poor linux support)


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: xenon481 on March 11, 2011, 05:42:20 PM
Judging from that pic, means that you need to make your own guides for it from plastic, or even make it travel out of the back and then over the case and out.
http://i.imgur.com/kIoH7.png

By trying to force the air to change directions by 180 degrees, you would be adding a ton of airflow resistance to the "inside the case" card exhaust. That resistance would cause a (relative) high pressure zone on that side of the card. The high pressure zone would cause the majority of the airflow to go out through the "outside the case" exhaust and thus the majority of the air to flow over the "outside the case" GPU and a significantly smaller amount to flow over the "inside the case" GPU.

This is nearly the equivalent of pointing an inflow fan (which is very likely to exist right in that area of the case......) directly into the "inside the case" card exhaust. They do nothing but fight eachother and make everything worse in total.

In a worst case scenario, this could even cause a resonating normalflow/backflow which would cause hot air to stagnate on top of the "inside the case" GPU.

Such a cover device would cause MAJOR problems for the card.

The only proper solution for this extremely significant airflow design is to change the lower forward intake fan to instead be an exhaust. You will then need to find another way to flow cold air intake into the case. Both to the intake of the GPU and the CPU... Doing this in many cases would not be a trivial task.


Title: Re: Now that the 6990 is out....5970 or 6950 still the way to go? Building a box
Post by: Syke on March 11, 2011, 07:22:23 PM
The only proper solution for this extremely significant airflow design is to change the lower forward intake fan to instead be an exhaust. You will then need to find another way to flow cold air intake into the case. Both to the intake of the GPU and the CPU... Doing this in many cases would not be a trivial task.
I would put intakes on the side of the case, with exhaust fans in front, back, and top.