Mapping THE Milkyway Galaxy requires a significant level of precision, to, i think, more than 16 places of decimals.

The way computer single precision is implemented will only give around 11 or 12 decimal places. this means the science cannot be carried out, unless the hardware is capable of double precision.

So, the GPU implementation of this project is only for ATI and nVidia cards capable of double precision, and the ATI GPUs have had this facility for several years. Even the Fermi nVidia GPU implementation has the double precision capability limited (crippled).

I am sure I will be heavily corrected by more knowledgeable posters, but I think this is the gist of the case?

You are definitely right about the precision necessity of the project. The double precision is necessary for the accuracy. Afaik, the single precision is accurate to 6 decimals, double precision is accurate to 12 decimals. I don't know about the 16 decimal precision though:)

Double precision binary floating-point format
Double precision binary floating-point is a commonly used format on PCs, due to its wider range over single precision floating point, even if at a performance and bandwidth cost. As with single precision floating point format, it lacks precision on integer numbers when compared with integer formats. It is commonly known simply as double. The IEEE 754 standard defines a double as:

Sign bit: 1 bit
Exponent width: 11 bits
Significand precision: 52 bits (53 implicit)
The format is written with the significand having an implicit integer bit of value 1, unless the written exponent is all zeros. With the 52 bits of the fraction significand appearing in the memory format, the total precision is therefore 53 bits (approximately 16 decimal digits, ).
Source:
http://en.wikipedia.org/wiki/Double_precision

There are also issues like floats on GPUs aren't IEEE 754 compliant. They have the same binary format, but operations aren't so consistent. They don't support all 4 rounding modes, signaling NANs and some other things which aren't so important. More importantly, they don't support denormal numbers which get flushed to zero.

Maybe there are other pointless

Sorry..but I meant to say "Maybe there are other projects that support my card,because those two that u've sujestec are pointless.

Actually, Fermi's solution to double precision is much less crippled than ATI's approach to it. One thing Nvidia did cripple somewhat was its capability in the consumer line of Fermi cards due to the lack of ECC by reducing the double-precision to 1/8 that of their pure Tesla GPGPU Fermi cards. The performance in benchmarks shows that even that it's stated that the performance has been cut to 1/8, benchmarks show that is really only around 1/3 of the amount of performance loss. It all has to do with memory.

Only all 58XX and up cards have double precision.

I find this an unfortunately incomplete statement.

All ATI HD48xx and HD38xx series cards have double precision implemented and can successfully crunch Milkyway work quite readily.

When the server runs constantly, I have had an HD3850 crunching Milkyway work for over a year.

You miss the point posted earlier someone stated that 56xx and or 57xx are capable of doing double precision
Apart from the 5XXX list the capability list is almost complete.
Anthony only needs to add the 5830 and then maybe some fermi stuff when the problems are fixed.
And yes many older models are DP capable as allready mentioned in the list, i just reacted on this 5xxx issue.
I myself have some older models running but the newer 55xx/56xx/57xx no longer have DP, its so sad for us that ati decided the remove DP on these lower models.

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Its new, its relative fast... my new bicycle

Bad news for Laptop owners with ATI graphics:
most of the ATI Mobility HD cards do not support doubles. This is even true for the new Mobility HD 58xx models.

(See ATI Knowledge base)

The only exception seems to be the "Mobility Radeon HD 4800" Series.

Both my ATI Radian 5830's work.
Just depends on what type of Motherboard one has.
The xfx 630i motherboard with a Hd 5830 does a milky way in 1Min53sec with a mild overclock.
The Intel 31dg with a Hd 5830 does a Milky way in 2Min00sec with a Mild overclock.
Both running at 68-69c.

Should I crank it up a little more on the overclock???

I am not sure but it seems to me that the cypress models all overclock well and easy
The way i overclock is to load furmark let it run at 1024x768 windowed in test mode not as benchmark and then watch the average/max fps
And i look for artifacts or errors, while i crank the card up with msi afterburner, there are other tools but i hate them ( traytools/atitool/riva tuner )
Now the core overclock is pretty straight forward you crank it up till you see either artifacts or when the machine freezes or reboots, when it does lower it like 10mhz from the point it crashed and try again, if again happens you found your limit on the core.
The memory on the newer cards is somewhat different since these cards correct themselfs you watch the fps of furmark.
Everytime i crank the speed up with 10 mhz and keep my eye on the fps if they keep going up your on the right track but if they become equal or lower then you found the limit. again lower 10mhz and try again if same result your found the limit. Now on most cases i test after i set these settings i start try major benchmarks for a day or 2 to see if the machine stays stable.
If it does remain stable then most overclockers do a step back 10 to 20 mhz and keep that as the final setting.
There seem to be ways to crank up voltage on these cards also, but thats not my thing (since there is a big change of blowing up your card)

Overclocking does give some minor increase of performance, to be honest they are really so small it hardly worth doing except for bragging to friends about the good syntetic benchmarks

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Its new, its relative fast... my new bicycle

dcushing wrote:

Both my ATI Radian 5830's work.
Just depends on what type of Motherboard one has.

Maybe we have a misunderstanding here ...
The "Mobility HD" models are different from the "normal" Radeon HD cards. They are build into laptops, as a fixed part.
A major difference is, that most of these "Mobility HD" laptop graphics chips do not support double precision. This has nothing to do with Motherboards and overclocking..

For the first time I have a gpu that can run this......time to go get a mil.

As far as I can see there is no Linux client for ATI GPUs. Is there any chance of getting that? I am currently running Collatz, but would love to do something more meaningful...

Hi, got a Juniper HD5770, Single Precision, though, also an 4850 which is
capable of doing Double Precision

It sure is a pitty, MW has no S.P. app.'s, but the 4850 does well, probably replace it for a 5850/5870 or 5900 series.
How much power they need to operate as I had some issues getting the GTX480 going, taking 15A on it's 8 pin, 15A on it's 6 pin connector and 5 or more through the Mobo. And they run quite hot, 85-95C (!)
According to spec's, that shouldn't be a problem and it isn't, only needed a 850W, instead of 650Watt.

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Knight Who says Ni

Those FERMI cards, just installed a GTX480 & GTX470 on an ASUS P5E with an QX9650
CPU, they are 'Double Precision', since it isn't mentioned in the spec's?

Anyway, they are fast, very fast.

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Knight Who says Ni

Those FERMI cards, just installed a GTX480 & GTX470 on an ASUS P5E with an QX9650
CPU, they are 'Double Precision', since it isn't mentioned in the spec's?

Anyway, they are fast, very fast.

How fast?

They natively do double-precision FP operations and the GTX460 is rated at 907 GFLOPS. That's at the 675 MHz clock speed. I am currently running mine at 850MHz completely rock solid crunching Collatz WUs in the ~600 seconds/WU range. And it doesn't even phase Aero performance on Windows 7. Temp is currently at 66C with fan speed at around 70%.

I would argue that they currently blow anything ATI has out there away barring the dual-GPU cards. they haven't even introduced a "full" Fermi card that has all 512 CUDA cores enabled. They are working with TSMC to get the wafer yield up and power consumption. The GF104 was a giant leap forward in thermal efficiency, power usage, and overall performance. Let me put it this way:

"When this baby hits 88 miles per hour, you're gonna see some serious shit."

With regards to the ati/nvidia duel. My 5970 will do a Collatz on each core in 330 to 360 seconds. That's almost twice as fast as the 460. Yes I have mine sitting at 900MHz (stock is 750) without trying. I suppose I'm glad it's winter as it sits at 61/71°C (GPU0/1) with the fan at about 60% on Collatz. Temps go up by 4°C to 5°C with MW (84 sec/wu/gpu) and another 2°C to 3°C on dnetc.

My old 4870 does a Collatz in 800 seconds.

So I think nvidia have a ways to go before they blow ati away.

Sorry to disappoint you Mutiny32, but I agree with TGG on the current position with ATI cards and nVidia GPUs that can run any ot the following projects - Milkyway, Collatz and DNETC.

When I run Collatz on my current ATI HD5850 GPU the individual WUs are seen off in under 410 seconds. This GPU will see off a Milkyway WU in <110 seconds.

This card is not the top ATI card currently - with the HD5870 and the dual HD5970 able to crunch faster again. Again, come November the ATI band wagon will roll on to it's new architecture with the release of the HD68xx cards soon. Rumour has it that these will be in the order of 70% faster than the equivalent HD58xx series cards. But this is all rumour. Mind you, rumour also has it these will be seriously expensive as well.

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Go away, I was asleep

460 is a nice improvement on the nightmare NVidia are battling, but its a way way away from the claim being made.

A simplistic benchmark, but common one says it all:

Ultra 460 Benchmarking V ATI Cards

The card benchmarked is the fastest 460 on the market today, but still cant compete at the required level. A look at the chart for "standard" 460's shows the norm for the 460 class - which has a hard time against the low end 5830, let alone its direct competitor the 5850. Given that the 460 is in the new NVidia Fermi technology offering Suite, and the 58xx class is 2 + years old, there should be a much closer fight - there isnt, Fermi was leapfrogged by 58xx before it was even off the drawing board. As was said above the AMD (ATI)6xxx are due release 4th Quarter this year. NVidia are already behind, 6xxx will leave them for dead.

I hope Fermi2 - son of fermi - whatever they call it, improves markedly, else competition out there will be a one way street to AMD (ATI brand name has been dropped), such a lead is bad news for pricing. Therefore despite returning to the AMD (ATI) fold for the first time in 20 years, I furvently hope NVidia get their act together, but on current track record I am not holding my breath.

Regards
Zy

One area that nvidia does have on ati is the stability of their drivers when gaming. I don't have an issue when crunching but on my now superseded 4850 it would regularly freeze or cause a system reboot when my son was playing Star Wars Battle Front 2 or when I was playing Need For Speed. Haven't played these on the PC since I got the 5970 and updated the driver, but that was a frustrating period.