Posts by Saul
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1) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13837)
Posted 2096 days ago by Saul
Edit: The data bus I was referring to in the previous post was: 64-bt floating pointp (fp)capable GPUs have a 128-bit bus and the 32-bit fp capable ones a 64-bit bus.

I just wanted to add that most GPU project are changing to OpenCL as a universal platform for both ATI & nVidia both had their own: CAL & CUDA, respectively. So GPU's talking should refer to maximum data bit width like when refering to CPUs, but that is not the issue in most, if not all, GPU projects that use GPU's fp for calculations refer to the fp capability requirements of the volunteering GPUs unfortunately, hence the switch to focus on fp numbers in GPU talk in most forums.

In CPU talk, 32-bit CPUs have a 64-bit fp Unit (FPU); in 64-bit CPUs the FPU is 128-bit, but in GPUs it seems that 32-bit GPUs have 32-bit fp, I could be mistaking in this part. In the ATI Radeon™ HD 4600 Series GPU Specifications You read 128-bit fp for all operations, I think this means 4 32-bit separate numbers that can be send into the Video Card, I was told this by a AMD person a while ago by e-mail but it doesn't seem to be the meaning in the spec webpage.

Anyway, I was trying to clear my point.
Cheers.
2) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13829)
Posted 2097 days ago by Saul
@mikey:I don't doubt you have experienced, I already saw your 1 time signature you posted, no need to indicate me to click on your profile to show off me the same thing and yes I have clicked on some profiles not only in this forums but in many and you're not the first one making huge amount of points/projects, but my point still stands about the developer part.

My 2 ATI 4670s are don't have 64-bit floating point (fp) only 32-bit so is not suitable for many GPU projects that might use CF so I can't experience them and searching forums to find out about CF performance on GPU crunching will be very time consuming; I'll let that to faith. However I know about computer architecture enough to tell you that CF not only let's you work with 2 + GPUs but it adds more bandwidth (5 Gbps) to communication between video cards besides the PCI-E 2.0 bus (also 5 Gbps or more), so if the GPU crunching is slower is not in the bandwidth, maybe the is just not optimal code.

You might have not yelling at me but your attitude tells me otherwise and yes as Crunch3r wrote, using CAPS and '!!!!' is impolite on the Internet.


@Crunch3r: Sorry, but there is such thin as 32-/64-bit GPU WUs it doesn't refer to the data bit length, as is in CPUs, but to the fp precision; if this projects uses integers well I think most GPUs can handle that.

Luckily as you write if this is a integer-only math project and I can participate, most GPU crunching are protein folding which uses 64-bit fp, most if not all other GPU projects also use 64-bit fp.

The ones that used to use 32-bit are changing to 64-bit because of OpenCL 1.0 specification, my GPU supports only partially OpenCL 1.0, it supports OpenCL 1.0b (beta), which is a little behind the official first official 1.0 spec. (1.1 is out and 1.2 in in beta-testing). I don't know if 64-bit flops GPUs have bigger integer capability than 32-bit flops GPU though, may be since their data bus is twice as wide.
3) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13816)
Posted 2099 days ago by Saul
SO now you think you'll have an authority by yelling at me? grow up...
Well Moo is a stupid project IMO, not worth investing CPU/GPU time. If they do it slower well maybe that's their fault, maybe they're not doing it right, that's only the first reference to CF GPU crunching I have so I'm not convinced by your experienced, you shouldn't either if it's also your first reference.
4) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13809)
Posted 2100 days ago by Saul
@Mikey: you misunderstood, I'm not saying CF helps in the current state of collatz, what I'm saying, again, is that if developers choose to use CF to use 2+ GPUs as a way to explore WU processing acceleration that something you don't know, so you don't have the technical authority to say if it'd be useful or not.

@terencewee*: No matter how experience he has crunching he doesn't have a say what the devs can or can not do about CF and if you were misunderstanding like mikey did and you were referring to CF crunching possibility then the above paragraph explains it.

I'm grateful with the info that was relevant to my question and I did said so.
5) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13791)
Posted 2103 days ago by Saul
CrossFire(CF) makes 2 cards work as 1, and I'm running 2 WUs, which means collatz is not using CrossFire. Your suggestion about testing with it on and off makes me think that you don't know if CF would have a improvement on collatz from the developer POV, so let them affirm or deny if this, what you write is your opinion and nothing else at the seems, if you know better explain me in detail, I love technical details.
6) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13783)
Posted 2105 days ago by Saul

CrossFire makes both gpu's act like one gpu, that doesn't make for faster crunching but it does make for MUCH faster gaming. Transferring the data between gpu's takes time and that makes for slow crunching.

I know what CrossFire does, so if it works for games it should work for GPGPU, since it's 5 Gbps CrossFire bridge accelerating processing, of course it takes time, every synchronization in the PC takes a few cycles to adjust the transfers but this is not different: it takes the minimum amount of cycles to synchronize, it should work for anything, hence my exploring suggestion.

And YES projects CAN tell what kind of card you have and send you the best workunit they have for your particular pc/gpu.

Is not always the case I recently added a protein project and it failed and restarted after a few seconds, after a few fails it took another WU, this is when you get a 64-bit WU into a 32-bit GPU. I removed the project of course, that's why I made this question here, I was afraid I'd be successfully and wrongly crunching a 64-bit WU with my 32-bit GPUs
7) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13769)
Posted 2106 days ago by Saul
I really hope the project can tell which cards are 32-bit and which are 64-bit and can have WUs for both, I can't afford any hardware right now, if that is the case I'm glad.

The mini collatz WUs are the ones that abort the most. No problem with dead lines, I'm crunching WUs doe in 6 days from now.

I tell BOINC to stop collatz project when using a 3D game/app, because even in no-3D apps. it causes lag. Well I'm using both GPUs so if they are used by collatz with CrossFire or not that's OK with me as long as both my GPUs are used, maybe collatz could be accelerated a bit by using CrossFire/SLI, I think this project should explore that possibility.

Thx for the reply.
8) Message boards : Windows : I have 32-bit fp GPU, is it good for collatz? (Message 13759)
Posted 2107 days ago by Saul
A yes or no would do. I hope I can help, I have 2 Crossfired ATI HD4670s. I'm running collatz in both GPUs and it gives lots or aborted by project WUs, I'm reading Supported ATI Cards and Lot of ATI errors threads. The AMD Supported Cards says my card is supported so I met collatz system requirements but it also states clearly it does not support 64-bit fpops. So I ask if collatz have 32-bit fp WUs? or am I just incorrectly trying to crunch 64-bit WUs?




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