Asus X550VX rev 2 and Vram type

[jasko_jacker]

Asus X550VX nvidia error 43, before replacing the graphics chip, having an identical card, I try to replace the vram. The voltage of the vram on the card is 1.35V but while this card uses Elpida W4032BABG VDD = VDDQ = 1.6V / 1.55V / 1.5V ± 3% and 1.35V ± 3% the donor card uses samsung 4KG41325FC-HC03 K memories : POD_18 (1.8V, 1.8V)
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How is it possible

[SMDFlea]

Re: Asus X550VX rev 2 and Vram type

The ninth character is an F so its F:POD_15 (1.5V,1.5V)

4KG41325FC

[jasko_jacker]

Re: Asus X550VX rev 2 and Vram type

ok
thanks but not 1.35 (dual voltage as elpida) ?
The dc/dc is a up1565p , which provides two (fixed ?) voltages, 1.5v and 1.8 so what I didn't understand about 1.35v ?

[SMDFlea]

Re: Asus X550VX rev 2 and Vram type

Is the donor board the same revision,what part numbers on both are at PU9301

[jasko_jacker]

Re: Asus X550VX rev 2 and Vram type

It's very strange, both use up1565p not in fixed mode (pin 6 is not to GND) , resistor divider is 10k (pr9312) and 11.8 k (pr9313)

[SMDFlea]

Re: Asus X550VX rev 2 and Vram type

ok
thanks but not 1.35 (dual voltage as elpida) ?
The dc/dc is a up1565p , which provides two (fixed ?) voltages, 1.5v and 1.8 so what I didn't understand about 1.35v ?

The The up1565p is adjustable as well. In the X550VX boardview pin 6 is connected to a resistor divider

https://pdf1.alldatasheet.com/datash...P1565PQKF.html

Edit: i was looking at the boardview and datasheet,you posted before me .

[jasko_jacker]

Re: Asus X550VX rev 2 and Vram type

vram voltage = 0.75(1+(11.8/10)) = 0.75(2.18) = 1.635 v
With these resistors value, the output should be around 1.5V
but the boardview (version ?) and my reading is 1.35 v , on the asus site I see a model upgrade (x550vxk).
probably there is something that I do not understand but since the cards are identical also for revision I change the vram elpida with the samsung

[SMDFlea]

Re: Asus X550VX rev 2 and Vram type

what are the resistor values on the donor board

[jasko_jacker]

Re: Asus X550VX rev 2 and Vram type

it's the same 10k and 12k with these values and using the formula on datasheet the result should be around 1.5v and not 1.35