Seller Note “Owned from new and only used for gaming. Turned pc on one day and it just stopped working hence spares/repairs.”
- I really like the ichill cards, so quite interested in this one
- It’s this one https://www.techpowerup.com/gpu-specs/inno3d-ichill-gtx-1080-x3.b3635
- Cosmetically appears fine, resistances fine, not detected, missing VCore, VMem & PEX, usually like this kind of fault, hopefully a fixable circuit issue. Let’s see!
- Resistances (seem normal)
- Vcore – 0.4Ω
- VMem – 114Ω
- PEX – 64Ω
- 1.8V – 898Ω
- 5V – 8.55KΩ
- 3.3V – 350KΩ
- 12V – 1.7MΩ (slot) 4K+Ω (8-pin EXT) 5.7MΩ (6-pin EXT)
- After discovering the physical damage on the back of the card (missing components and corrosion), this card is likely considerably more challenging to fox than I first though.
Investigating missing VCore
The voltage sequence on Pascal cards is 5V→ 1.8V→ VCore→ VMem/PEX, so VCore is the first area to look at. The PWM is the usual uP9511P https://pdf1.alldatasheet.pl/datasheet-pdf/view/1222413/UPI/UP9511P.html
Want to check:
- 5V on VCC (pin 12) – present
- 3V on EN (pin 36) – missing
- 2V on Vref (pin 2) – present
OK, next investigate logic gate U506 (similar to SN74AHCT1G08), the output of which is Vcore EN
It has Vcc of 3V, output Y is 0V, as expected due to missing EN, input B is 1.8V (correct) and input A is 0.637V, which is too low, I am guessing this should be more like 3.3V.
Input A is from PS1_NVVDD_EN_PROT, which requires several conditions to be present.
Checking PS1_NVVDD_EN_PROT sources:
- R627 (should be a 10K resistor) – should feed in NV3V3
My suspicion is the NV3V3 is an issue.
Physical damage and corrosion discovered
Again, I should have checked more before investigating the circuity, it’s pretty clear to see. It’s going to likely make things a lot harder.
Some areas are just very dirty and it’s hard to tell whether there is damage or just corrosion. I will clean up where I can.