I am doing an analysis of my three GPUs, comparing their credit delivery performance, one against the other.

1. All WUs completed within 24 hours. That's why the 750Ti does not appear in the Gerard numbers(!)
2. The Gerards are from 23 April, when I installed the 780Ti, and the Noelias are from 10 June.
3. Any % improvement difference between the 'ETQunbound' and '467x' Noelias is very marginal.
4. There are fewer 780Ti and 750Ti WUs than you might expect. But these two GPUs are on the same rig, and I have been sharing the Gerard loads between them so that all WUs complete inside 24 hours. None of these WUs are in the analysis.

My conclusions?

• The 780Ti is only around 33% better than the 770 for GPUGrid. Big surprise, given the price differential.
• 2x750Ti deliver more credits than one 780Ti, provided they can complete in under 24 hours; i.e., no recent Gerards! I've not done the sums, but the price difference is staggering.
• Perhaps the 'best bang for the buck' is an external device that will support many 750Ti GPUs, if Gerard can be persuaded to moderate his processing demands... Is there such a thing??

• 2x750Ti deliver more credits than one 780Ti, provided they can complete in under 24 hours; i.e., no recent Gerards! I've not done the sums, but the price difference is staggering.
• Perhaps the 'best bang for the buck' is an external device that will support many 750Ti GPUs, if Gerard can be persuaded to moderate his processing demands... Is there such a thing??

You need to use a "zero buffer size" by setting the resource share to 0, as discussed here:
https://www.gpugrid.net/forum_thread.php?id=3986

You need to leave at least one CPU core free for each card. In fact, I run two GTX 750 Tis on each of two PCs (four cards total). This gives me essentially two cores for each card, since each card uses only about 20% of a core on my Haswell machines, leaving the rest of the core available for either card that needs it. (This leaves the other 6 cores free for other BOINC work.)

Finally, you may need to do a moderate overclock, something I normally avoid, but these cards can take it; my ASUS GTX750TI-OC-2GD5 don't get about 64C with a 1348 MHz GPU base clock, and I have received no errors yet.

https://www.gpugrid.net/results.php?hostid=223541&offset=0&show_names=1&state=0&appid=
https://www.gpugrid.net/results.php?hostid=194224&offset=0&show_names=1&state=0&appid=

The GTX 750 Tis are not good, they are great for efficiency, which is especially welcome during the summer.

It is quite possible for the GTX 750 Tis to complete the Gerards reliably in under 24 hours

Not sure why GPUGrid penalises me for having a poor connection, but that's the way it is!!

Not sure why GPUGrid penalises me for having a poor connection, but that's the way it is!!

Is it too much to ask that the project give credit based on WU processing time rather than sent/received time?

Thanks for this very interesting report, tomba, and thanks for sharing.
Really appreciated :)
____________
[CSF] Thomas H.V. Dupont
Founder of the team CRUNCHERS SANS FRONTIERES 2.0
www.crunchersansfrontieres

Thanks for this very interesting report, tomba, and thanks for sharing.
Really appreciated :)

Thanks for this very interesting report, tomba, and thanks for sharing.
Really appreciated :)

Perhaps the 'best bang for the buck' is an external device that will support many 750Ti GPUs. Is there such a thing??

Thanks for the reply, skgiven!

Enabled SWAN_SYNC and rebooted

overclocked to 1306/1320MHz

Which sliders do I use to get to 1306/1320MHz ??

Enabled SWAN_SYNC and rebooted.

Did that. Task Manager now tells me that my two acemd.847-65 tasks are running at 100%.

Which sliders do I use to get to 1306/1320MHz ??

"GPU clock offset" slider. Boost bins are in 13MHz intervals. Begin by raising one bin at a time until you reach 1306 or 1320.

At you're current 1.2V/1150MHz clock -- +156MHz (on the GPU clock offset slider) equals to 1320MHz which is a total of 12 boost bins. If you stay under 80C the boost clock should stay at 1320. If not - clocks will fluctuate a few bins. This is normal. Unless EVGA program is incorrectly reading out voltage - 1.2V/1150MHz might not leave alot headroom for an overclock.

A bit puzzled why GPU-Z says I'm only at 1147...

1147MHz is the clock without boost. Click the GPU-Z Sensors Tab to see what it actually is.

Enabled SWAN_SYNC

On the down side:
...
The 750Ti’s might not hold their value as long and IMO being smaller would be more likely to fail.

If the size of a tasks increase then there is a likelihood that the 750Ti will no longer return work in time for the full bonus. That said they should still get the 25% bonus (for reporting inside 48h) and could run short WU’s for some time.

Noticed that your 750Ti temperature crept up to 82C:

# GPU 1 : 79C
# GPU 1 : 80C
# GPU 0 : 69C
# GPU 1 : 81C
# GPU 0 : 70C
# GPU 0 : 71C
# GPU 1 : 82C

Suggest you reduce your temp target a bit.

I cannot increase the power usage of my GTX750Ti, unlike the 970’s.

Second hand £120 to £160 vs £210 to £240; roughly £140 vs £225.

That's why I don't recommend GTX 750Ti for GPUGrid. This card (and the GTX 750) are the smallest ones of the Maxwell series, and since there is the GTX 960 it's a much better choice taking all three aspects (speed, price and energy efficiency) into consideration.

I cannot increase the power usage of my GTX750Ti, unlike the 970’s.

A custom vBIOS could help. (Maxwell BIOS tweaker tool and NVflash) I would always hit a powerlimit when clocks were around 1320Mhz for GERALD's so I flashed. A lot of 750 series are set at a 38.5W hard limit . At 60W = 157% of the original BIOS power cap.

Robert, the custom vBIOS referred to below is for the GPU not the motherboard, so it won't help you out. Your only solution is a different motherboard/system.

An MSI Z77A-G45 (and many similar boards) has 3 x16 PCIe slots, and you could additionally use up to 3 of the PCIe X1 slots (albeit at a performance loss of 15% or more depending on setup).

I doubt there's room for more than one GPU on an x1 and that would have to be single-width.

Powered PCIe Risers :)

When you start using risers it's gone way past basic closed case design. It's very much an open case/bench worktop design.

On June 23 I reported this comparison of my three GPUs:

Tomba - thanks again for sharing.

Here is a Gerald credit/power rating:
Average credit/hr divided by the (GPU) BTU/h

(250W) 780ti (853BTU/h) = 23.6 credit/h per BTU/h. (credit/hr = 20190)
(230W) 770 (784BTU/h) = 19.3 credit/h per BTU/h (credit/hr = 15135)
The 780ti has 18.3% higher credit/h per BTU/h

(60W) 750ti (204 BTU/h) = 43 credit/h per BTU/h (credit/hr = 8849)

The 750ti/770/780ti together = 44208 BTU/day or 1842BTU/hr.
All (540W) GPU's together have a 24.4 credit per BTU rating.
The 770 is bringing down the overall average due to power hungry dynamics.
Maxwell's credit per BTU rating is >50% higher than 770.

Average credit/hr divided by the (GPU) BTU/h

The British thermal unit (BTU or Btu) is a traditional unit of energy equal to about 1055 joules.

The BTU is often used to express the conversion-efficiency of heat into electrical energy in power plants. Figures are quoted in terms of the quantity of heat in BTU required to generate 1 kW·h of electrical energy. A typical coal-fired power plant works at 10,500 BTU/kW·h, an efficiency of 32–33%.

At the bottom is my post of 6 July. Since then I have continued to monitor the performance of my three GPUs.

A feature of these past 2+ months has been the narrow ranges of credit delivery, by GPU and WU; NOELIA & GERARD, illustrated by the standard deviation percentages below. So I am confident that, for me, the percentage comparisons are truly representative.

Final conclusions?

* the 780Ti has been a big disappointment. Much less than 2x the 750Ti and only 22% to 25% better than the 770.
* SWAN_SYNC does little for the 780Ti but much for the 770 and 750Ti
* wish I had some more-recent GPUs to put through their paces!

On June 23 I reported this comparison of my three GPUs:

On June 27 I made some changes:

Rig 1 - 780Ti & 750Ti:
Activated SWAN_SYNC and upped the 750Ti GPU clock from 1150 to 1275.

Rig 2 - 770:
Activated SWAN_SYNC.

Here are the numbers since those changes:



Noelias:
10%+ improvement on the 750Ti, 15+% on the 770 just with SWAN_SYNC, and only 4% on the 780Ti.
The 780Ti lost 12 percentage points against the 750Ti
The 780TI lost 13+ percentage points against the 770(!) How can this be since the only changes relative to these two GPUs was SWAN_SYNC on both...
Even with a faster 750Ti, the 770 gained 6 percentage points against it.

Gerards
The 770 gained 8%+ from SWAN_SYNC, the 780Ti only 4%+.
The 780Ti lost 5 percentage points against the 770.

Summary:
OCing the 750Ti gives, for me, 10% more credits.
SWAN_SYNC is a worthwhile freebee, especially on my 770: 15%+ more credits on Noelias and 8%+ more on Gerards.

With four GTX 750 Tis set up as I indicated above, my RAC has now stabilized at 1,059,238.69 PPD, or 264810 PPD/card. Each card draws 90% of TDP according to GPU-Z, or 54 watts per card. So each card yields 4904 PPD/watt.

I know that is significantly above my GTX 960 when I tried it, and now use that card on POEM or Folding. But the 128 bit memory bus on the 960 (the same as for the GTX 750 Ti) seems to limit it here, and also on Einstein as I recall.

EDIT: If you look at the 960 on a value basis, it is a very good card, and it is still very energy-efficient as compared to the others; nothing beats the Maxwells that I have found. I just happen to have the 750 Tis and need to find the best use for them in the projects I support.