Broken R7 260x - Voltages on board
Hi everyone.
I got a broken MSI R7 260X for $10, seller said there was a surge and afterward graphics and network stopped working.
The power supply goes into protection if inserting the 6pin ATX12V into the graphics card.
So i figured, well, yeah, some mos broke in the VRM, should be easy fix.
Indeed, a Hiside mos was shorted and i replaced it.
The Vcore was generated by 2 switcher groups (hiside + loside MOS and an inductor in each group) powered from 12V PCIE and another 2 from 6pin 12V ATX. The broken mos was on the 12V ATX side.
There's another 2 switchers from 12V PCIE which i guess is Vmem or mem controller.
There's also one switcher from 12V ATX which is either Vmem or mem controller.
The motherboard gives 1 long beep and 12 short ones with this card so there are some more problems.
I measured some voltages on the board and i have ~0.9V for Vcore and the other switcher from PCIE.
The switcher from ATX12V has 1.6V.
These seem a little low but the card is not doing anything so maybe it's in low power.
The fan starts spinning maybe 2s after powerup.
Are there other voltages to be measured ?
Since it doesn't post, maybe it's the bios not initializing.
Any advice is welcomed since graphics cards cost an arm and a leg nowadays.
I got a broken MSI R7 260X for $10, seller said there was a surge and afterward graphics and network stopped working.
The power supply goes into protection if inserting the 6pin ATX12V into the graphics card.
So i figured, well, yeah, some mos broke in the VRM, should be easy fix.
Indeed, a Hiside mos was shorted and i replaced it.
The Vcore was generated by 2 switcher groups (hiside + loside MOS and an inductor in each group) powered from 12V PCIE and another 2 from 6pin 12V ATX. The broken mos was on the 12V ATX side.
There's another 2 switchers from 12V PCIE which i guess is Vmem or mem controller.
There's also one switcher from 12V ATX which is either Vmem or mem controller.
The motherboard gives 1 long beep and 12 short ones with this card so there are some more problems.
I measured some voltages on the board and i have ~0.9V for Vcore and the other switcher from PCIE.
The switcher from ATX12V has 1.6V.
These seem a little low but the card is not doing anything so maybe it's in low power.
The fan starts spinning maybe 2s after powerup.
Are there other voltages to be measured ?
Since it doesn't post, maybe it's the bios not initializing.
Any advice is welcomed since graphics cards cost an arm and a leg nowadays.
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