Suggestion: DO NOT POWER 8kX at 12V! 8K X USB to a Power Supply Adapter Works Fine and Saves a USB Port!

Same for me, though i should have read more thoroughly - thought he was using a 12v powered USB adapter to get the 5v out of that adapter, never thought a out actually providing 12v to the HMD.

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Re opened topic as the issue has been corrected.

im using these for my basestations.

would this work on the headset?

For the 8kX it needs a 5v source. In a molex connector the red wire is the 5v. However only mod if you know what your doing and accept all potential perils.

https://images.app.goo.gl/FVxPW5QPKpAoezpK7

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Im reading this thread and Im thinking to myself …

shouldn’t this be obvious?
what am I missing?
did Pimax break standard again and use a custom voltage for USB?

but no…it seems like this is a PEBUAO* error.

*Problem exists between user and outlet. :wink:

Kind of makes you wonder about these claims about the area by the displayport feeling super hot.

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Not really as there are many whom mistakenly think if a plug fits it works. A friend’s GF fried a tablet.

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Yeah most people shpuld be aware of basic electronics, as it is used in everyday life.

if they dont know it I would probably not trust them around a wall socket.

Your friend should buy some proper food then… :woozy_face:

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The same could be said with household cleaners and we have many injuries and deaths because folks are unaware cleaner A mixed with Cleaner B results in unforeseen consequences and not a better cleaner.

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#Dadjoke 202020202020

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:smiley:

It was that or: “As long as it’s deep fried it should be fine…” :slight_smile:

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To be clear, I’m using a small iPhone wall adaptor that outputs 5v/2.4A.

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Those motherboard that comes with 3.1 USB, 3.2 usb…are those 5 volts and can it be used?

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Yes… :+1::upside_down_face:

TLDR - for the thread; Just don’t do weird custom power adapters without knowing which voltage it provides. If unsure stick to any USB port (if it doesn’t provide enough power it won’t work but nothing fries)… :wink:

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I do not think so.
It needs another USB powered connector on the PC (or the USB charger). What is worse, 5V is a low voltage to power anything, so it means high current, which means in consequence higher voltage drop over the long cable.

USB 3.0 default max current is 900mA as mentioned already, which times two gives you max 9W (2 x 4.5W). I would expect that this would be a borderline to operate two 4k displays at high refresh with the high speed DP bridge and MIPI and that the headset is power starved.

I would also expect that this is the real reason why only one USB add-on is allowed and that even that would not be reliable.

Here is a table with voltage drops over the USB cable of different quality just for illustration.

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… but it’s still more versatile as it can be plugged into a wall charger or a power bank if used with a back pack etc.

I’m not saying it’s the perfect solution… :wink:

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Even for a “powerbanking” you would be far better using 14.4V “laptop battery”, if only for the higher voltage. There is a difference connecting the backpack with a short cable (which is however not the case for the consumer version, which I believe comes with a long one) and connecting the default long cable to the wall charger. Using 5V is literally the worst choice you can make for the power voltage.

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What I’m trying to say is that using USB is something regular people understand… :upside_down_face:

Custom plugs and custom voltages etc. doesn’t exactly make the product more user friendly.

I’m kinda hoping they thought about power consumption incl. modules when deciding on the new cable.

If not, I’m sure a lot of people will let them know… :rofl:

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Hopefully their choice of using a USB instead of a power block is NOT the reason that all the headsets are running hot where the cable plugs into the HMD.

I asked support about it, and they said it’s normal and that as long as it’s not hot on the lenses it’s fine… except its gotten so hot on the top of the HMD where the cable plugs into it, that i couldnt keep my fingers there for more than 3 seconds.

I actually ordered an IR Thermometer to check the temperature where that cable plugs into the HMD, because it’s not normal that it gets that hot. I’m also not the only person that said theirs is running hot also.

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I highly doubt it. Modern electronics all run at 3.3V or lower internally, and high speed electronics like those used for DisplayPort translation need extreme voltage stability. Invariably a low-dropout switching PSU is provided. Pimax may well have gone with buck-boost so they can step up the voltage.

So, something like 60degC. Now if the temperature really is that hot, it is unlikely to be normal.

Unfortunately the way most of these work makes them insensitive to very small very hot spots. You might get a much higher temperature reading with a thermal camera like the FLIR One.

Two things might make the PSU unusually hot. New design features, or defect.

I suppose it is possible Pimax designed their PSU to provide multiple step up voltages for powering such things as high-voltage LED strings. That might involve multiple regulators, maybe even some linear regulators. Linear regulators following on from the switching regulator to smooth things out might have been necessary for the higher speed electronics to support the 8kX resolution stably, and would explain a lot of extra heat.

Manufacturing defect is possible, but then you apparently went and plugged your 8kX into 12V without asking anyone first whether it was safe to do so. You could easily have overstressed an inductor or capacitor, making the PSU much less able to transfer packets of energy across these components.

If the temperature in that region - and only that region - really is that hot, you can scrape away a bit of the rubberized coating and stick heatsinks on with thermal epoxy. Ideally a heatsink with a fan attached.

I don’t know how much Pimax can help you if you really did apply excessive voltage to the 8kX. I would think tat is pretty much ‘warranty void’.

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