Does the CPU affect the speed of the GPU?

[bruce]

[I am just a user like you, I have never had a PC with 8 GPUs. this is rumor]

F@H attempts to reserve a CPU thread for each GPU to move data for it across the PCI-E bus, so ideally you would have a 8 threaded CPU.

Your CPU only has 2 threads, so is overwhelmed by 8 GPUs. A 'faster' CPU will not help as much as a multi-core CPU.

Your existing CPU is described as 'Mobile' which may mean upgrading the CPU on the existing Motherboard is not possible/difficult.

@ Meki01 Try this:
* Remove all but two of the GPUs.
* Reinstall fah, removing data. (First write down your name/team/passkey so you can reinstall them.)
* Observe the speed of the first two WUs downloaded. How does that compare to what you've been getting?

The points that FAH awards are highly dependent on the speed of completion and if the WUs expire, you earn no points.

I know nothing about how cybercoins are awarded; only how FAH points are awarded. This forum supports FAH only and we will gladly help you earn the maximum number of points. The cybercoin folks run their own websites.

[Joe_H]

The GT 730 4 GB is a Fermi device which means it only supports OpenCL 1.1

Not necessarily, a Kepler based GT 730 with 4 GB of RAM was also available. Providing the output of FAHClient --lspci would show which GT730 variant you have based on its PCI device ID number. The log file showing the first couple hundred lines will also show whether it sees a Fermi based card supporting OpenCL 1.1 or the Kepler card supporting OpenCL 1.2.

[toTOW]

Each card now works with around 4,200 PPD and requires around 14 hours for a WU.

It seems low ... Did you setup a passkey ?

https://test.foldingathome.org/support/ ... s/passkey/

[Jupis_folder]

I must do something wrong. I use a PCIe riser with PCIe 2.0 x1->x16 (x16 only mechanical), and have no performance penalties on a GTX1050Ti.

For a very small protein, the performance penalty of 1x will be small enough that you probably won't notice. For a larger protein (with more atoms) the GTX1050ti will definitely be choked for data. What project(s) are being assigned and how many points-per-day are you getting. I run several 1050Ti's in 16x slots with at least 1 free CPU thread per GPU.

The word "definitely" may be only theoretical. To be more accurate: I run 2 GTX1050Ti of the same manufacturer, bought at the same time as the same model, in the same computer.
One is in the x16 slot and on in the riser slot, which is parked at a book behind the computer case. I run this setup since november 2020. All the time, there were no noticable difference in PPD, both cards have a range (depending on WU) from 250 to 420 kPPD. Fun fact: Until now, the 420 kPPD is only reached by the card in the riser, the other card at the internal x16 slot did not exceed 390kPPD.
As the temperature of both cards is always around 60°C, I assume the is also no heat penalty at one of the cards.

[Meki01]

Thanks for the info, I'll try a card in a "normal" system and compare the values.

So, I have now tested a GeForce GT 730 on an ASUS motherboard. Only one slot was occupied by the GT730. PPD = 11,698 compared to approx. 3,900 in the 8 slot board. So a significant increase, even though the Asus board is only powered by an Intel G2030 @ 3GHz. So it's really down to the 8-slot board, which is only equipped with PCIE 2.0 x 4. When I get the different 8-slot board (with PCIE 3.0 and exchangeable CPU - it will be an [email protected]), I will test the whole thing again and post it here. Thanks for the many tips and hints!

[Meki01]

Each card now works with around 4,200 PPD and requires around 14 hours for a WU.

It seems low ... Did you setup a passkey ?

https://test.foldingathome.org/support/ ... s/passkey/

Yes, a passkey is set!

[Meki01]

[I am just a user like you, I have never had a PC with 8 GPUs. this is rumor]

F@H attempts to reserve a CPU thread for each GPU to move data for it across the PCI-E bus, so ideally you would have a 8 threaded CPU.

Your CPU only has 2 threads, so is overwhelmed by 8 GPUs. A 'faster' CPU will not help as much as a multi-core CPU.

Your existing CPU is described as 'Mobile' which may mean upgrading the CPU on the existing Motherboard is not possible/difficult.

@ Meki01 Try this:
* Remove all but two of the GPUs.
* Reinstall fah, removing data. (First write down your name/team/passkey so you can reinstall them.)
* Observe the speed of the first two WUs downloaded. How does that compare to what you've been getting?

The points that FAH awards are highly dependent on the speed of completion and if the WUs expire, you earn no points.

I know nothing about how cybercoins are awarded; only how FAH points are awarded. This forum supports FAH only and we will gladly help you earn the maximum number of points. The cybercoin folks run their own websites.

Thanks for the info, I was never interested in cybercoins, I thought this board would be great for F@H. Unfortunately, I am not so familiar with the matter ... Since I get another 8-slot board (a better one), I will try again with this one. I will post the results of the test here. Thanks!

[iero]

Any 8 slot motherboard, it would seem to me, that it would be a mining one, thus, running into the same issue. Even x99 boards with 40 lane cpus have 4x PCIe slots running at PCIe 3.0 x8 speeds each.

[gunnarre]

So it's really down to the 8-slot board, which is only equipped with PCIE 2.0 x 4.

The AliExpress listing says they are PCIE 2.0 x1, not x4. Is that not correct?

[Meki01]

So it's really down to the 8-slot board, which is only equipped with PCIE 2.0 x 4.

The AliExpress listing says they are PCIE 2.0 x1, not x4. Is that not correct?

It looks to me, purely optically, like an x4 ... but I'm not a specialist ... How many lanes would have to go to the connector with an x1 and an x4?

[Meki01]

Any 8 slot motherboard, it would seem to me, that it would be a mining one, thus, running into the same issue. Even x99 boards with 40 lane cpus have 4x PCIe slots running at PCIe 3.0 x8 speeds each.

Okay, since the board is already on the way, I'll try it anyway ... more about that when the board is there ...

[gunnarre]

It looks to me, purely optically, like an x4 ... but I'm not a specialist ... How many lanes would have to go to the connector with an x1 and an x4?

An x1 has 36 pins (2 times 18), and an x4 has 64 pins (2 times 32), but note that even if the slot is x16 and might have copper pins for all the pins, it might still only connect the 36 pins for a PCIe x1 connection to the actual chipset and CPU. The unused pins are just used to hold the card in place mechanically, or to simplify production. They might supply power though, since it's a mining board, so the data lines might be dead but still carry power on the power lines.

[Meki01]

It looks to me, purely optically, like an x4 ... but I'm not a specialist ... How many lanes would have to go to the connector with an x1 and an x4?

An x1 has 36 pins (2 times 18), and an x4 has 64 pins (2 times 32), but note that even if the slot is x16 and might have copper pins for all the pins, it might still only connect the 36 pins for a PCIe x1 connection to the actual chipset and CPU. The unused pins are just used to hold the card in place mechanically, or to simplify production. They might supply power though, since it's a mining board, so the data lines might be dead but still carry power on the power lines.

Mechanically there are x16 slots, unfortunately I can't understand it electrically ... Is there a test or a software to determine that?

[iero]

Having the cards under load, run GPU-Z and on the Bus interface field look for the value after the @. For example, my RTX 3060 reads: PCIE x16 4.0 @ x16 3.0 . That means that my card can run at PCIE x16 4.0 but currently runs at x16 3.0(due to my motherboard). Like wise you can check your speeds.

[Meki01]

Having the cards under load, run GPU-Z and on the Bus interface field look for the value after the @. For example, my RTX 3060 reads: PCIE x16 4.0 @ x16 3.0 . That means that my card can run at PCIE x16 4.0 but currently runs at x16 3.0(due to my motherboard). Like wise you can check your speeds.

Thanks for the support! GPU-Z shows: "PCIe x8 2.0 @ x1 2.0". This means that the card can run under PCIe 2.0 with x8, but only runs with PCIe 2.0 x1. Correctly? So apparently the board can really only do PCIe 2.0 x1, as you have already mentioned several times ...