Don't think that is an issue, the seller of the rig has a picture with a green light on the sata drive and no battery and is running fine. I also found out i had to put in all of the power connectors, done that and found out the real Power SW, done that as well. Same result, no signal! Driving me insane just for a product to "add GPUs." Which i expected to be done in 5 minutes, not 5 weeks.
Thanks all for your help, if worse comes to the worse, there's a PC repair shop just round the corner, I'd probably get in there, and see if they can fix it if this board can't. Worth a go myself, before getting a new item fixed! hahah
So you have a second hand mining board an "eth70 b75 v1.01", i have never owned or touched one but i offer the following:
A link to its spec page translated:
https://www-dngiot-com.translate.goog/proinfo/mineboard/4.html?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=nui#supportA link to the spec pdf which says something about (12) lots of sockets for 24 pins atx and (13) auto on but i cant see any label for 13 on the diagram.
https://www.dngiot.com/static/instructions/mineboard/ETH_B75_V1.01.pdfAs i said having little experience with this but some with similiar embedded mobos and i can confirm the IGFX can die which could cause a no post scenario. I'm not saying this is your problem please study the links above and try get the manual to determine power switch operation. However given you have followed seller advice and still not working then would it not be wise at this stage to return it as DOA?
Regarding the battery, i have seen plenty of dead or low cmos battery prevent a post but never a missing battery prevent it but it might happen i suppose and quick one to check. Be weary of pound shop CR2032 they are all fake and last a week but will work for that week lol.
If I had this problem and was not able to return it then I would do the following:
1. Press the power switch using something conductive on the pins of the mobo PWS header VERY CAREFULLY after reading the manual to satisfy myself i know where the power switch header is.
2. Determine if motherboard posts - use a plug in anaylizer already suggested and resolve the fault it shows if possible which could be as simple moving RAM around and even making sure all chips are seated correctly. If you have more than one stick of RAM then use each seperately to determine if one is faulty.
3. Determine if the psu is working correct so with system on carefully use a dc voltmeter to check cpu power connector at the mobo end and 24 pin atx power or simply get a good known psu to test the mobo with and even then check the voltages as a mobo fault could pull down voltages.
Then
If power is present and correct values measured and reaching the mobo and its not a RAM problem preventing post where noting else is connected to the mobo then you have ether a damaged mobo or damaged cpu and remotely possible corrupt cmos or bios chip.
To rule out CPU fault get a known working compatible socket LGA-1155 and test.
If CPU ok and you really want to get into fixing it then a usb chip programmer to read the bios chip and verify its contents are correct. also measure the voltage at the bios chip to rule out that problem.
Finally if not able to return it I would consider reseating the heatsink of the IGFX as in time the thermal paste gets old and crusty its possible that the GPU died already and i think they are none user replaceable being soldered to the board i.e. integrated. Before tampering with it discharge
your own static by grounding and then place a finger on the heatsinks and power on, do they get any heat at all - it gives a clue....
I have revived some intel boards by reseating IGFX heatsinks but the damage is done and they usually die pretty quickly as been overheating for a while and the IGPU on these can be the culprit but im not saying it is.
Happy hunting.