[Help!] Akitio Thunder2 and Power Overload: A Cautionary Tale
 
Notifications
Clear all

[Help!] Akitio Thunder2 and Power Overload: A Cautionary Tale  

 of  5
  RSS

Plastixx
(@plastixx)
Trusted Member
Joined: 4 years ago
 

You have the benefit of being able to look at your other working PCB. Use a meter to ohm out the connections so you know where to run wires on the dead board.

The MOSFET only has three connections you need to trace out. Pins 1,2,5,6 are the drain pins (connect them all together), pin 3 is the gate, and pin 4 is the source.

2011 17" HP ENVY 17t-2100 [2nd,4C,Q] + GTX 1050 Ti @ 4Gbps-mPCIe2 (EXP GDC 8.4) + Win7 [build link]  

ReplyQuote
Plastixx
(@plastixx)
Trusted Member
Joined: 4 years ago
 

I was on my phone earlier, but looking at your pic on my PC I can clearly see the connections. The two large drain and source traces are very obvious. The gate looks like it goes to that thin trace near it going diagonally,  but double check it with a meter.

You can run wires from the 4 drain pins to the right side of that large ceramic capacitor if you need to. If the pad near the source pin is blown out, you can scrape some of the green resist off the trace and put a jumper wire in the middle of those 4 vias (the line I drew). Use the largest gauge solid copper wire as you can fit. It will take a lot of heat from the iron to get solder to flow on that thick trace.

 

 

connections
2011 17" HP ENVY 17t-2100 [2nd,4C,Q] + GTX 1050 Ti @ 4Gbps-mPCIe2 (EXP GDC 8.4) + Win7 [build link]  

Yukikaze liked
ReplyQuote
Yukikaze
(@yukikaze)
Prominent Member Moderator
Joined: 4 years ago
 

Thanks for the detailed overview. I'll try to see if I can make some sense out of this tomorrow, but I am not keeping my hopes up too much.

Want to output [email protected] out of an old system on the cheap? Read here.
Give your Node Pro a second Thunderbolt3 controller for reliable peripherals by re-using a TB3 dock (~50$).

"Always listen to experts. They'll tell you what can't be done, and why. Then do it."- Robert A. Heinlein, "Time Enough for Love."

 
2012 14" Lenovo Thinkpad T430s [3rd,2C,M] + RX 550 @ 10Gbps-TB1 (Atto Thunderlink) + Win10 [build link]  


ReplyQuote
Plastixx
(@plastixx)
Trusted Member
Joined: 4 years ago
 

Post a close-up pic of the damaged area if you can.

2011 17" HP ENVY 17t-2100 [2nd,4C,Q] + GTX 1050 Ti @ 4Gbps-mPCIe2 (EXP GDC 8.4) + Win7 [build link]  

ReplyQuote
FricoRico
(@fricorico)
Eminent Member
Joined: 4 years ago
 

I'm not sure if the power relay modification might actually help you, but I think it does protect users from frying their Akitio boxes with more demanding GPUs that suck a lot of power through the PCIe slot. This is not actually a mod I came up with and is something people have been experimenting with over at the other forums.

This particular setup has been advised by Goalque to me. I don't think that Akitio's advice to only have a bigger power source into the barrel plug is very wise, because you basically run out of spec of the board.

In my setup I don't do any taping tricks and the board is not powered by the J4 cable bridge any longer. It involves some difficult soldering though.

First I remove the cable going from J4 to J2 on the Thunderbolt board, this cuts the power from the boards MOFSET.

I also soldered in C3 and C4, which are basically to stabilise incoming power from the barrel plug. Not really needed, but for some cards it can make a difference in stability.

Now for the hard part, where I connect two thick wires from the underside of J6 to A1, A2, B1, B2 on the PCIe slot. My cables came from a donor power supply that was broken, they are really thick making it hard to not overlap two pads and getting enough heat in them without melting the insulation. I created a bridge between A1 -> A2 and B1 -> B2 with some solder, but it is not particularly required.

To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.

.

3RYL, Yukikaze and goalque liked
ReplyQuote
Yukikaze
(@yukikaze)
Prominent Member Moderator
Joined: 4 years ago
 

To be honest, I gave up on this piece of PCB.

I bought a 199$ open-box Thunder2 to replace the fried one, and due to a lucky twist of fate got it for really cheap. It was advertised with all peripherals, but was missing the TB cable, and I ended up being refunded nearly 50$ for the cable and its potential shipping, making the whole thing around 150$ minus the cable, which I obviously have from the dead one. I am going to mod the dead casing into a shell for larger cards, and move PCBs around as needed depending on the card(s) I run.

As for my investigation: The thing is that the GTX750Ti's, at stock, power draw under Furmark is 66W. Since my card is modded to increase TDP, it is not surprising that I managed to pull over 75W through the slot and fry the Akitio's power-circuitry into a crisp.

The conclusion of the story here is that people should be very careful with Furmark (which is already documented as dangerous to video cards themselves) in the Akitio, especially with cards that have no other means of power but pulling power through the slots. Assuming you overclock, you should use non-max-stress stability testing, such as running 3DMark or other engine benchmarks and just don't overclock as aggressively, unless you know how your card draws power. Tom's Hardware GPU reviews sometimes provide information on the power draw of cards from the slot 12v and 3.3v rails as well as the extra 6/8-pin power-cabling, so that is something you can rely on. From what I've seen, higher end cards, with good voltage delivery systems, and multiple 6/8-pin power connectors, tend to draw most of their power from these connectors, often drawing only a token amount through the slot itself. It is the cards that lack external power, or are skimpy on the external connectors that are the riskiest. Unfortunately, often times they are the most useful cards for eGPU because they can be run in the enclosure as is. Someone who might overvolt, overclock, or BIOS mod theirs is likely putting their Thunder2 at heightened  risk of fiery failure.

For example, this Asus GTX950, lacking external power, draws 75-76W through the slot at gaming loads. Overclock it and you're out there in the twilight zone. I suspect the GTX1050/1050Ti are also in this risky category.

It is also interesting to note that the GTX1080FE and the GTX1070FE are actually drawing quite a bit of power through the slot. The Titan X (GP102), in comparison, is actually pretty tame in this regard.

As a side note, the Fury X barely needs slot power at all.

Want to output [email protected] out of an old system on the cheap? Read here.
Give your Node Pro a second Thunderbolt3 controller for reliable peripherals by re-using a TB3 dock (~50$).

"Always listen to experts. They'll tell you what can't be done, and why. Then do it."- Robert A. Heinlein, "Time Enough for Love."

 
2012 14" Lenovo Thinkpad T430s [3rd,2C,M] + RX 550 @ 10Gbps-TB1 (Atto Thunderlink) + Win10 [build link]  


ReplyQuote
FricoRico
(@fricorico)
Eminent Member
Joined: 4 years ago
 

Other than that you can often also modify the behaviour of the GPU power consumption with BIOS changes. I investigated this endeavour hoping to fix power issues that the RX480 had without the driver fixes that were implemented later on.

Still I'm curious if my changes to the PCB made any difference to protect the PCB from power overloading. I believe that the PCB is no longer responsible to supply the GPU of power, which is now done by the PSU directly because of the mod.

To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.

.

ReplyQuote
Yukikaze
(@yukikaze)
Prominent Member Moderator
Joined: 4 years ago
 

You can probably check this with a multimeter, tracing the load on the different components. That is definitely beyond my realm of knowledge, however.

Want to output [email protected] out of an old system on the cheap? Read here.
Give your Node Pro a second Thunderbolt3 controller for reliable peripherals by re-using a TB3 dock (~50$).

"Always listen to experts. They'll tell you what can't be done, and why. Then do it."- Robert A. Heinlein, "Time Enough for Love."

 
2012 14" Lenovo Thinkpad T430s [3rd,2C,M] + RX 550 @ 10Gbps-TB1 (Atto Thunderlink) + Win10 [build link]  


ReplyQuote
goalque
(@goalque)
Noble Member Admin
Joined: 4 years ago
 

Here’s my latest power bypass mod, without the cable bridge. One thick wire soldered to three +12V corner spots from J6 +12V. I used a piece of heat shrink tubing.

 

AKiTiO power bypass

automate-eGPU EFIapple_set_os.efi

Mid 2015 15-inch MacBook Pro eGPU Master Thread

 
2018 13" MacBook Pro [8th,4C,U] + Radeon VII @ 32Gbps-TB3 (ASUS XG Station Pro) + Win10 1809 [build link]  


Barts, Leeroy, ikir and 1 people liked
ReplyQuote
Leeroy
(@leeroy)
Active Member
Joined: 3 years ago
 

I fried the same module just less than two hours ago. Fortunately the PCB was not burnt and I'm able to power the GPU with a powered PCI-E riser.

I'm wondering if the power bypass mod will do the same job...

To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.

.

ReplyQuote
 of  5