bcunje

@Agoneous , if you are willing to open your laptop one more time, clipping/disconnecting the sense pins on the fan will cause it to run at max speed all the time.

It might be possible to custom fab a PCB with the traces lined up to the pins, but that in itself might not have a solid connection to the Ultrabay plug... It's unlikely that any standard PCIe slot/port would work because they are huge in comparison and the pin pitch is much larger.

Upon further inspection, the only way that I could get a clean PCIe 3.0 x4 interface would be to use 8 SMA coaxial connectors. I don't think there are any other connection types that support that kind of bandwidth and are in my price range. On the other hand 8 SATA cables, each one sending/receiving one lane with twinaxial cabling should be able to handle a PCIe 2.0 interface just fine. 8x PCIe 2.0 will be sufficient. Not even sure why I've gone and researched this yet since I have yet to even unlock to BIOS! EDIT: Oh yeah, I can't use SMA right angle connectors because they are a few millimeters too large to fit into the Ultrabay. EDIT2: Micro coax is an option (DC-10GHz), but is also expensive...

Type in "40025_Compal_LA-8692P" into google and it's the first result. I have SLI GT750M's in my laptop, but the only performance bottlenecks are the GPUs. They run hot, and in SLI I get the inevitable frame stuttering... I'm going to be developing on an Oculus Rift DK2, so I just need more GPU power. Frame stuttering in VR would be nauseating!!!

Nice find, however the Ultrabay connector is completely proprietary. It LOOKS like a normal PCIe connector because of the key notch, however it is not. There's 30 pins (15 each side) on the smaller half of the Ultrabay connector and only 22 (11 each side) on a traditional PCIe connection. I wish it was that simple!!! Also, the HDD caddys and disc drives do not have functioning Ultrabay connectors. They are just plastic blanks .

You're right, a x4 PCIe 3.0 bus would be more than sufficient. However since I'm going to be designing this entire eGPU system from the ground up, I'm going to add in lines for the other 4 PCIe lanes, especially since it's not too much effort to implement them anyways. I'm going to use a SATA interface to extend the PCIe bus because it looks like it will be the easiest to match trace lengths, it's cheap, and it's definitely up to the task. Each SATA cable will implement a single PCIe lane which means 4 cables for the x4 and 8 cables for x8 connections. There will also need to be an extra SATA cable for the CLK/CLK#, and I guess the SMBus data as well. This is all totally achievable and I don't mind getting my own PCBs fabricated. But first thing's first, getting rid of the Lenovo GPU whitelist. I can test this because I have another Ultrabay GPU which is technically not compatible with the system, so I will be able to tell whether or not the GPU passes the whitelist or not. I will try my best to keep updated on my progress in the other thread (http://forum.techinferno.com/diy-e-gpu-projects/5943-egpu-possible-lenovo-ideapad-y510p.html). I might need to source some of the expert's help to modify the BIOS if I'm unable to do it... Only time will tell! This is an exciting project . Edit: I've only for 4 inches of space to work with, so that leaves me with 5 SATA connector widths 4x PCIe 3.0 it is!

That's a shame... The Lenovo Y410P has 8x PCIe 3.0 lanes, so it looks like I will just have to design the board myself. I was hoping to just save some time instead of doing PCB fab from scratch. Since HDMI lines aren't good enough for the LVDS lines, perhaps I'll look into something else more readily available. Maybe SATA3, USB3, or DisplayPort Lines...? I am pretty certain their specifications are <6MT/s though... Oh well I'll figure it out! Thanks @Tech Inferno Fan !!!

I am going to be using the Ultrabay 8x PCI-e bus within the Lenovo Y410P laptop. I am going to be modifying the BIOS to remove the GPU whitelist, and I have a spare Ultrabay connector. Since Ultrabay provides 8 PCIe lanes, I wanted to know if there were any eGPU solutions that have 8 lanes implemented. If there are, it would save be some time and make the PCB fabrication of the Ultrabay connector slightly easier. Let me know!!! Thanks in advance

This is going to happen... Just need to do some more reading, familiarize myself with this particular assembly instruction set, and remove the function call. I'll probably just modify svl7s y410p BIOS to start with. Interestingly enough the 1.07 and 3.05 BIOS' have different strings for the GPU lock. Hopefully there's a y410p flash recovery procedure for when I inevitably break it!

Figured out how to remove the PCI-e whitelist for GPUs within the BIOS. It's essential an assembly jump loop that locks you into a screen that says "Please remove hardware". Simply jump out of the loop and you're good. I also have a spare Ultrabay connector that I can de-solder from a [working] GN35. This will happen but I need some time to custom fab a PCB with LVDS lane extensions as well as to modify the BIOS.

Google: "40025_Compal_LA-8692P" Again, the only issues with the setup are: ultrabay connector scarcity and PCI-e lanes 8-15 not being accessible due to Lenovo whitelisting.

Does anybody know if the new unlocked 3.05 bios lifts the Ultrabay GPU restriction? Last I recalled, it does not. Perhaps there are some new unlocked settings within the bios which will allow it to be unlocked?

@allstone I was able to get a pinout the the ultrabay connector, and it is totally possible. Interestingly the controls for the fan on the Ultrabay GPU are sent through the ultrabay connector X). The only data transactions between the motherboard and ultrabay are PCI-e LVDS 8x lanes and SMBus data. I'm assuming all the stupid whitelist info goes through SMBus. If svl7's bios removes the GPU whitelist, then this is as simple as re-purposing ultrabay connector by "chip-quik-ing" it and replanting it. All the necessary PCI-e pins exist there EXCEPT for the JTAG (optional) and hot plug detect (bypassable). On the Lenovo side of things, most of the other signals are power enables, power good, temp sense, fan speed, and fan tach. Voltages present on ultrabay connector are 3V, 5V, and 19V.. and we really only need the 3V. If the bios mod doesn't allow for GPU whitelist, then an option would be to capture/hold the SMBus with and FPGA or something and falsify the output to allow it to pass. Using a logic analyzer would allow us to see the fine details of the data bus transaction. @svl7 you may be interested...?

@allstone, I've got a GN35 (650M Ultrabay) that I unsuccessfully was able to convert into a 750M, mostly for experimentation. I was able to turn a GT755M into GT750M by modifying the hardware straps and reflashing it, then SLIing it with my onboard GT750M. The GN35 works perfectly fine, but I wouldn't mind goring it apart to experiment with an eGPU via Ultrabay connector. The only REAL issue is getting past the Lenovo whitelist. The Lenovo whitelist is why you can't normally slip a GT755M into a GT750M laptop, hence the need to change the hardware straps to change the Device ID. Just reflashing the card with a different Device ID will NOT allow the card to pass the Lenovo whitelist check. Do you know if svl7's latest unlocked 3.05 BIOS removes ultrabay GPU whitelist as well as wlan whitelist? If so, I'm going to get the desoldering the ultrabay connector and reverse engineering the pinout. Let me know.

@svl7 I was wondering if you could possibly take a look at the differences between the 650m and 750m vBIOS. I tried sifting through the two, but wasn't able to get my modified GT650M Ultrabay to work with a different vBIOS...