Detect chip with CH341A

I’ve already flashed many EPROM with my CH341A programmer without problems (with software v 1.8).
Now I’m in troubles with a detecting of Winbond chip model 25x20 CLNIG.
Is it possible to modify the internal database or upgrade programming software in order to read my EPROM ?
I need to read this chip bios that is positioned on a graphic card NVIDIA k2100m that I’ve to reflash.

You mean 1.18, I assume?

Please give me full model name of the Winbond chip that is giving you issues now, I will let you know what software version that may be best to use, or if maybe you should use ASProgrammer etc.
You may need to also try flashrom too (in Linux)

Yes you are right, my sw version is 1.18 ! … Stamped on chip there are the following characters: - WINBOND 25X20 CLNIG 1417 -
I’ve already tested with As programmer v. 1.4.1 in wich there is listed W25x20CL chip but I’m not able to read firmware (after reading are listed only FFFF characters) !
After several google finding I’ve discovered that for a CH341A programmer (my is the black version), there is a problem of output voltage when it is used with cable and clip, and there is a fix in order to workaround the problem !
Now I’ll try to understand if this is the real problem …

Hi check your connection from chip. I have same like FF FF FF when you have bad connect pin so when you have a good you see like : 0x C8 40 16

@Rhino - Yes, connection needs to be perfect, sometimes with cheap clip it can take 10+ attempt before it’s just right. Are you clipping the chip, or have the chip off board into a spring or other adapter?

You may have to try Linux/Flashrom, or here there is windows GUI version of flashrom you could try too
[Guide] Using CH341A-based programmer to flash SPI EEPROM (34) (Post #510)

Voltage is not an issue with black/gold CH341A, this is incorrectly spread information, propagated by posts like this (I used to think same too when I first looked at these programmers years ago)
You can do the mod/fix if you want, but it’s not necessary, people use these all day long with 3.3V chips, and MANY have tested with DMM, only 3.3V is put out to chip, there is not a voltage issue.

Many thanks @Lost_N_BIOS for useful suggestions that I appreciate and try to follows.
Today I’ll perform many other trials taking more accuracy when I’ll take a clip programmer on video card chip…
I’ll be inform you about my progress.

You’re welcome, and good luck!
Is this laptop card? If yes, yu may need to remove chip from the card, or leave card in system if possible and connect it’s main battery and PSU (don’t turn on system, just connect) - if the chip is in area where you can connect to it while card is installed on system.

have never tested this software

NVIDIA NVFlash with Board Id Mismatch Disabled v5.590.0
NVIDIA NVFlash with Certificate Checks Bypassed v5.287
Kepler BIOS Tweaker v1.27
NVIDIA NVFlash 5.590.0 or older also got dump support but i have not tested this program Before

if you looking for infromation for
GPU Variant: N15P-Q3-A1

hope this will help you

Today I’ve tried for long time to put in right way my clip programmer but without success !

This operation is needed for upgrading an old iMac with a new video card, for this reason I need to refresh the card with a “compatible” BIOS.
Just to be sure: after plugged in chip programmer into PC, is the “power” led the only that is turned on ?