Here's a small report of my eGPU setup using a Macbook Pro Retina 15 Late 2014 model.
Also integrating the OS internally with the eGPU inside the enclosure... all in one sweet package.
Specs:
2.2ghz Quad Core i7 4770HQ
16gb DDR3 Ram
Intel Iris Pro 1536mb Graphics
256gb PCI-e SSD Storage
Equipment:
-Magma Express Box 3T (Thunderbolt 1 Enclosure)
-Palit Nvidia Geforce GTX 960 2gb Graphics Card
-Marvell 88SE9230 PCI-e SSD card
-Sandisk Extreme II 480gb SSD
Now, the magma box 3t enclosure has 3 slots spare, after the thunderbolt uplink card, so that's space for a dual slot GPU and another add in card.
I've opted to add a Sata3 card in the that third slot. The Sata3 add in card I have, can have the 2.5" SSD mounted directly onto the PCB too.
It uses the Marvel 88SE9230 controller if that matters, and ordered it from AliExpress. This is the one:
Marvell chipset 2.5" SATA 6Gbps + 3 Ports SATA 3.0 PCI e Hybrid Controller Card HyperDuo SATAIII SSD + HDD PCI Express card-in Add On Cards from Computer & Office on Aliexpress.com | Alibaba Group
My installation process:
-Used Rufus to create USB install disc for windows 8.1
-Installed windows 8.1 via EFI boot. (iso is very specific to be able to boot the install, so tried around 5 different iso's before this worked)
-installed on to a empty 'MAC OS Journaled' partition that was created beforehand. This would be GPT ready so works perfectly for this UEFI install.
-Booted into windows, installed the latest Bootcamp Assistant Software. All Drivers are ready now. Even waited for all the windows updates after that to complete.
-Now, I had moved igdkm64.sys in the system32 folder, into the recycle bin so it wouldn't interfere (Not certain this is required). Then restored it back after the GPU had booted fine.
GPU cold boot procedure (plug and play thereafter):
-Magma Box power cable plugged in. Box is sitting idle but receiving power at this point.
-Thunderbolt plugged into the Magma Box end. Unplugged on the Macbook end.
-Turn on the macbook, reach boot options by holding down the alt/option key while booting.
-Wait 10-15 seconds plug in thunderbolt to macbook. Wait 2-3 seconds for the magmabox SSD windows, to appear in the boot options, and select it.
OS + EGPU in the Magma Box RESULTS
Now, I have a windows install on my internal macbook SSD and on the Magma box SSD inside the enclosure. This allows me to test both and show how much performance is lost using an OS + eGPU on the same thunderbolt line.
I will have some test's comparing a integrated install within the thunderbolt enclosure + eGPU with separated install as commonly done with windows inside the macbook's SSD and eGPU alone.
Initially we are aware that:
-The thunderbolt link for my setup is 10Gbps for thunderbolt 1. So performance could be improved with TB2.
-The SSD and eGPU will share this bandwidth down the single thunderbolt cable.
-This 'should' lose performance in games and benchmarks...but how much?
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Let's see the results:
Heaven 4.0 Becnhmark (Extreme Preset)
Integrated OS (Inside MagmaBox) + eGPU
FPS: 36.2
Score: 911
min: 18.5
max: 76.7
Separated OS (Inside Macbook) + eGPU
FPS: 36.5
Score: 919
min: 17.6
max: 75.0
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GTA V Benchmark (1440p Max settings)
Integrated OS (Inside MagmaBox) + eGPU
Average FPS
Pass0: 27.22
Pass1: 21.22
Pass2: 26.20
Pass3: 28.90
Pass4: 27.80
Separated OS (Inside Macbook) + eGPU
Average FPS
Pass0: 27.12
Pass1: 21.53
Pass2: 26.45
Pass3: 28.65
Pass4: 28.04
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3DMark11 (Performance Preset)
Integrated OS (Inside MagmaBox) + eGPU
Score P8480
graphics 8601
physics 9208
combined 6934
Separated OS (Inside Macbook) + eGPU
Score P8480
graphics 8601
physics 9210
combined 6927
Conclusion
From the above, it's easy to see negligible difference in performance using an integrated OS with the eGPU compared to the usual separate install.
This could prove that the links inside a 3 or more PCI-e lane enclosure, are separated between the slots. Therefore the bandwidth is always available for the GPU and SSD. This does also mean that these 3 or more lane enclosures will have slightly less bandwidth overall for the eGPU since they are spread throughout the other lanes (possbily 8Gbps).
But if the 3D performance is adequate, then no harm no foul. Overall a perfect solution for all in one OS with eGPU.
Peace.
*Note: The dip switch on the main board, was set to x4 link, Gen1 for the 3rd slot containing the SSD. This can be flipped over to x8/16, Gen2 if preferred to gain some extra speed on the SSD. This will be tested next to see if it affects GPU performance also.
SPECIAL THANKS TO NANDO4 FOR HIS WORK AND SUPPORT IN THIS ENDEAVOUR. MUCH APPRECIATED!