[SOLVED] Can't add a 5th gpu to my rig, black screen with no display

[DoruSonic]

I have an old board (asus AM1M-A) with an AMD 5350 that I've been using in a computer. It has 3 pcie slots

I bought a pcie splitter specific for mining (https://www.ebay.com/itm/284468350986) and it works when I have 4 cards connected. Doesn't matter if all 4 are connected to the splitter (using a single pcie lane) or 3 on the splitter and 1 on another pcie slot. All cards on risers

However, when I had a fifth card, the PC won't boot. The "press F2 for bios" appears but doesn't matter if I click F2 or not, black screen. I tried different combinations with 4 cards and it works, so all cards are working, the problem really seems to be having 5 gpus at once

The motherboard does not have a 4g enconding option, nor an option to set pcie gen. Tried to disabling most usb ports, serial and parallel ports, hd audio, svm and nothing. Is there anything I'm missing?

 

[helper800]

The computer is probably having issues with the amount of PCIe lanes and how to distribute them among the cards. Check the motherboard manual for the lane distribution for each slot. I would like to note that you are pushing old tech to do something that was never intended or something the engineers thought someone would try to do with the motherboard.