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Why is my Mac Pro 5,1 with GTX 780 slower on some games
- Thread starter Acceleroto
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usefull to note is that MacVidCards does offer a flashing and mod service for cards if you send it to him. That way the card would be setup to run properly and taking the lower PSU wattage that the Pro provides.
Using a 6 pin Mac Pro power cable might also help as I agree with the previous reply that the 6-8pin adapters are not always the right way to go. essentially you are telling the card that the 8-pin connector can draw more power than the system is specified to supply. In the short term this could cause the card to lower its speeds if detected properly, but in the worse case it could cause long term damage to the mac pro mainboard and the video card.
Using a 6 pin Mac Pro power cable might also help as I agree with the previous reply that the 6-8pin adapters are not always the right way to go. essentially you are telling the card that the 8-pin connector can draw more power than the system is specified to supply. In the short term this could cause the card to lower its speeds if detected properly, but in the worse case it could cause long term damage to the mac pro mainboard and the video card.
Flashed GTX 780s still draw more power than the Mac Pro was intended to provide. It's discussed a bit here.
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Wow, I sneak off for a bit & the thread gets busy! Thanks for all the posts everyone.
Those SATA plugs are plugged into the back 2 hard drive power plugs on the motherboard. I originally had it plugged into the optical drive power, but moved them to the motherboard to make shutting the case less work.
My CPUs are the stock 2.4GHz quad-core Xeons from 2010 (E5620).
So...if I want to stay on internal power, how should I be powering this thing?
Thanks!
I'm using the 2x6-to-8 pin adapter that came with the card to power the 8 pin and a 2xSATA to 6 pin to power the 6 pin connector. Here's that connector: http://www.amazon.com/gp/product/B007Y91B80/ref=oh_details_o02_s00_i00?ie=UTF8&psc=1
Those SATA plugs are plugged into the back 2 hard drive power plugs on the motherboard. I originally had it plugged into the optical drive power, but moved them to the motherboard to make shutting the case less work.
My CPUs are the stock 2.4GHz quad-core Xeons from 2010 (E5620).
So...if I want to stay on internal power, how should I be powering this thing?
Thanks!
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Not if it's properly modified. Basically, he flashes the card;s BIOS and lowers the clock voltages etc, so that it comes under the max power envelope. OP:
I'd get in touch with him for more details, but I'm also pretty sure that using that adaptor is not the greatest idea either..Once correctly flashed and setup, you will have the speed you want and safety as well. I'm pretty sure you could either send him the card ( he's USA based ) or sell the one you have now and buy another one that's correctly modified.
You didn't read what was discussed in the link I provided. Nor did you read what flowrider said. His MacVideoCard flashed GTX 780 was not under clocked.
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Yeah, it looks like @MVC is only about an hour drive from me. If I have to get it flashed/mod'ed I'm ok with that, but it'd be great if this thing would work correctly as-is.
That will be better but you need to cut some internals to route the cable...I'd still get a dedicated card. And since the OP is close to the source, I'd get it flashed rather than mess with cabling. I know they cost more, but you really do get what you pay for.
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Sorry, I missed this. Here are some CUDA-Z screenshots.
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Based on your first posts' Furmark score and Cuda-Z, your card is running as it should. EFI firmware will not help you improve your performance. Save your money and upgrade your CPUs.
If I were to power a video card with a 6-pin and an 8-pin connector, I would use one regular 6-pin to Mac 6-pin cable and one Mac 6-pin to 8-pin cable or use an auxiliary power supply, which is the safest way.
If I were to power a video card with a 6-pin and an 8-pin connector, I would use one regular 6-pin to Mac 6-pin cable and one Mac 6-pin to 8-pin cable or use an auxiliary power supply, which is the safest way.
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Thats mostly correct. Efi isnt likely to increase performance if its behaving like a 780 should. My concern would be the power draw.
If using 6-8pin adapters on the main oard headers; i'd be worried that under load the card could overdraw and possibly damage the card, mainboard and psu, or it could be smart and lower its clocks/cores in use to offset the power differential resulting in lower performance under load.
If it were me, i certainly would not want to take the risk.
The problem is that there's no way to tell the card how much power to pull from which connector. For example, even if the card were under clocked to pull a max of 210W, it won't pull 70W from each of the three power sources (6-pin power connector, 8-pin power connector, PCI-e slot) evenly. It could very well pull 50W from the 6-pin, 110W from the 8-pin, and 50W from the PCI-e connector. Each 6-pin connector is only rated to provide up to 75W and the PCI-e slot is also rated to provide up to 75W.
We have a 3.33 in our's, and although you might get a performance hit, my major concern is that power drain...asking for 300W without the mod wouldn't be something I'd do. Think LB as well as PSU and your into $$$
I don't think this is due to the 2.4 Ghz. I would rather hear how these things are powered before we go any further. If I have to figure out a way to put one of my PRECIOUS 2.26 Ghz Xeons in my Quad CPU tray I'm going to be peeved. (Don't think there are any YouTube How-To's for putting an IHS back ON a CPU) And I'd rather cut off a few toes than undo the 5680s in the Dual tray, so single CPU it is.
I wonder how I could mimic the thickness of the heat spreader? Some metal shims of some sort I imagine. Not really too worried about burning up the 2.26's, not a lot of demand for them.
So, OP, how are you connecting the 780 to power?
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Is that picture right?
Only 4 wires into an 8 pin plug?
Can't be right, it shows them going into a 6 pin.
Please take a pic of the actual plug you are using.
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That's what I thought...As far as I know asking the PSU for 300W on a non=flashed card, however you choose to connect it, is asking for trouble. With a flashed card ( such as you supply) the cores are automatically clocked No? This should eliminate the chance of burning out the LB or PSU.
I would imagine shims of the proper thickness would work fine...
I have a pair of W5580s that I found at a too good to pass up price coming. Once I have them installed, I can provide more info on how CPU MHz can affect the Heaven benchmark.
I didn't think that was right, so this morning I reran using the same settings, but in ML with Apple drivers.
Lou
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When conducting these comparisons, we try to keep all variables as similar as possible. Switching to different drivers is counter productive.
...and "Medium" instead of "Ultra"
Post edited. Sorry for the confusion. We OK now?
Lou
These results muddy the water a bit. flowrider's results are a bit better than jetjaguar's with all things being pretty much equal except CPU, where flowrider actually has a slightly slower CPU. Unless one of them has background tasks running, I can only deduce that with these settings, the GTX 780 begins to show its limits and where CPU is no longer the bottleneck.
Not definitely. To get full view we'd need to know what clocks jetjaguar's card has. Lou uses Gigabyte Windforce OC with Boost clock 1006 MHz and RAM clocked @1502 MHz. If jetjaguar's card is stock clocked one (i.e. 900 MHz Boost) it would explain why Lou results are slightly better despite the CPU clock difference.