View source for GTX 1080 PC turning on for split second, short on 12V repair

{{Repair Guide
|Device=GTX 1080
|Affects parts=Capacitor, VRM
|Needs equipment=multimeter, soldering iron, soldering station
|Type=Soldering
|Difficulty=3. Hard
}}
==Problem description==
GTX 1080 Zotac, PC not turning on or turning on for split second then turning off when the card is inserted. This particular case concerns a Zotac AMP EXTREME GTX 1080
[[File:20240410 104859.jpg|thumb|219x219px|Short circuit measurement on 12V_EXT (Figure 1)]]

==Symptoms==

*Whole computer not starting
*Card not powering up
*Fans flinch for a split second
*Short on 12V as measured by a multimeter
[[File:20240410 1155411.jpg|thumb|239x239px|Vcore VRMs (Figure 2)]]
[[File:Screenshot 20240410-105532.jpg|thumb|260x260px|Shorted capacitor close up view (Figure 3)]]
[[File:20240410 111249.jpg|thumb|189x189px|Replaced capacitors (Figure 4)]]

==Solution==
===Diagnostic Steps===

* Start by [[Nvidia Pascal (GTX 1000) GPU Diagnosing Guide|measuring the resistance of the 12V lanes]] (12V_BUS, 12V_EXT)
* If you suffer from the same problem, you should measure sub 100 Ohms on one of them, follow this [[Short on 12V rail on Pascal (GTX 1000) GPUs Repair|guide for potential shorted components]] 
** In this case, a short was found on one of the 12V_EXT connectors (Figure 1)
* After identifying which rail is [[Short Circuits - Repair Basics|shorted]], inject voltage (1V 10A) to localize the shorted component 
** The most obvious suspects are the VCore VRMs/MOSFETS shown in figure 2
*** However the actual shorted component turned out to be a capacitor on the other side under the Vcore VRMs. The culprit was C195. C196 looked suspicious as well. (Figure 3,4)<br />

===Repair Steps===
Simply de-solder the shorted capacitor. It is not strictly necessary to replace it. However, it's value and rating are 16V 10 uF 0603 package. If the source of the short is a VRM, then you must replace it!

After removing the shorted component, measure again to confirm the short is gone, if not, repeat the steps to find the other short.