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AMD Radeon RX 470 (Updated: 3-way CrossFire possible)

I bought an "XFX Radeon RX470 RS 4GB GDDR5 True OC 1226MHZ XXX Edition w/ Backplate HDMI/DVI/3XDP Graphic Card" from "ncix.com (Canada)" and installed it in my 3.33 6 core firmware upgraded 4,1. It works great. I'm getting very close to the same Unigine Heaven Benchmark results the orginal poster has.

I did have a problem with a proccessor board red led (the cpu one not the memory), and a red led on the 470, both lighting up, whenever I shut down the mac pro. And the two red led's would even stay on if I pull the ac power cord out of the mac pro.

The two red led's would go off once I boot up again. But while the two red led's were on (while the mac pro was off), I discovered I could also get them to turn off if I disconnected the displayport cables from the 470.

This was easyly googleable. And turned out to be just the "AddOn" brand displayport cables I bought for the card.

The problem is known as "the displayport pin 20 problem".

My Dell displays were sending 3.3 volts back out through the displayport cables on pin 20. Which was going into the 470 causing the two red lights to light up.

I now have on order some "Accell UltraAV B142C-007B-2 DisplayPort to DisplayPort 1.2 Cable with Locking Latches (6.6ft /2m)" displayport cables from amazon.ca that I read is a 19 conductor cable, with no wire for pin 20, for this very problem. There seams to be very few cables like this on the market I think.

In the mean time while I'm waiting for the Accell displayport cables. I learned from some photos with instructions, how to make a crude tempoary work around to make the cables work. By covering pin 20 at one end of the cable, with a long 2mm wide sliver of black electrical tape. And then carefully inserting the connector into the graphics card port.

It took about 3 attempts for each cable to get the tiny strip of tape to stay in the right place. Don't use metal twizzers unless the other end of the cable is for sure disconnected from any display.

It works fine. The red led's are off while I'm shutdown now. Which will get me by untill the Accell cables arrive.

The 470 is the best card I've ever had.

EDIT: The Accell cables are working fine.
 
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@Number Curtain, very good to hear you're having success with the RX 470. It really is the best value GPU atm for a Mac Pro tower.
 
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I installed GM today. RX 470 is fully functional after the kext mod. RX 480 still crashes in OpenGL. At this point, RX 470 is the better card to get for Mac Pro tower.
 
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Not that bad of a trade-off. I needed to disable SIP in order to use BootChamp anyway.

Got a great deal on an R9 280x last night off Craigslist. I ran benchmarks again in Sierra GM. Unflashed, RX 470 offers the same performance at half TDP.

I remember being able to run 2 x R9 280x was a big deal - lots of mods to make them work. With the RX 470, you can go to Best Buy/Mircro Center/Fry's, pick a pair off the shelves and that's all you need to do. 3 x RX 470s require a bit of work but that setup will beat GTX 1080 in certain tasks.
 
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Identical performance between unflashed RX 470 and R9 280x.

valley rx 470.png valley r9 280x.png
 
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was you able to get EFI boot screen without any flash ? or do you have to wait until drivers load ?
 
I did not remove it. I wanted to compare both as stock PC cards. I have another R9 280x with the resistor removed to test in the near future.
 
theitsage said:
I did not remove it. I wanted to compare both as stock PC cards. I have another R9 280x with the resistor removed to test in the near future.
Click to expand...

Curious, the RX 470 @ 5 GT/sec has the same 3D performance as a 2.5 GT/sec R9 280x then? I'll wait until you test the resistor-removed R9 280x.

Of course it's a minor quibble since it's already hard to find 280xes and soon enough 470's will sell for even more decent prices, but it does matter to me a bit since I run BOINC tasks with my un-modded 280x.

If you could run Luxmark 3.1 between all three cards in single fashion at some point, I'd appreciate it as the BOINC project I run supports OpenCL and currently I get better results with the 2.5 R9 280x than GTX 770's running full tilt with the web driver and CUDA.

Still kind of sucks that GM (was it 320 or 322?) needs to be modded with SIP disabled, but ehhh, we should consider ourselves lucky it works at all.. because it definitely points to Apple using the chip in a newer MacBook Pro which is all but confirmed at this point. It DOESN'T point to a new Mac Pro, necessarily. :(
 
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Earl Urley said:
Just curious, but did the R9 280x have its resistor removed for 5.0 GT/sec function?
Click to expand...

Since the 470 have roughly the same performance as the R9 280X, so, I think we can safely assume that even the mod is avail, there should be around zero performance gain in real world. In other word, no need to bother this.
 
FWIW.. The "working" OpenGL surface on the 470 has issues with lighting and OpenGL effects. No rendering issues with a 7950. Lighting issues are illustrated below with failed lighting on the player in the center of the screen.


Screenshot copy.png
 
To be expected since the driver used is for a different version of the chip. The only drivers in macOS are for the 460.
 
RX 470 runs slightly slower in an eGPU setup. I'm using a Dell DA-2 220W power brick with a Y splitter - barrel plug to AKiTiO board and 6-pin PCIe to GPU.

IMG_0900.jpg


Screen Shot 2016-09-17 at 11.14.16 AM.png


Screen Shot 2016-09-17 at 10.07.05 PM.png Screen Shot 2016-09-17 at 10.16.35 PM.png
 
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Earl Urley said:
Curious, the RX 470 @ 5 GT/sec has the same 3D performance as a 2.5 GT/sec R9 280x then? I'll wait until you test the resistor-removed R9 280x.
Click to expand...

Would be very little difference. The connection speed only effects how fast data is transferred to the card. But in those benchmarks all the data is already loaded into VRAM (if there is enough) and the internal processing power of the GPU and compute cores are barely effected.
 
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jacek_zet said:
o yeah! rx470.rom attached by theitsage bricked my GPU.
Click to expand...
You cannot currently flash any RX 460, 470 or 480 with a Mac EFI at the moment because quite simply...it doesn't exist.

As @666sheep says, if you want one then you're going to have to write it yourself. The ROM file that was attached was purely as a starting point to potentially get the process started. Why you decided to flash the linked ROM to your RX 470 without either fully reading or understanding the process and information that has been provided is somewhat puzzling.

What is currently possible, is adding the PCI ID to AMDRadeonX4100.kex to enable full acceleration and Metal support. This is what the blog post of @theitsage talks about.

I hope you find a way to recover you RX 470 and get it all working once again. Hopefully you purchased a model with a dual BIOS.
 
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