Question mobo AGP fault? Lost Display, Disabled GPU and sometimes 1 long 3 Short Beep


Jan 14, 2010
Hi i am trying to find whats wrong with my set up
been using this PC for almost 3 years,
mobo : gigabyte b450 pro
cpu : amd ryzen 3600
memory : corsair 2 x 8gb 3200 dual channel with xmp on
gpu : asus rx580 8gb
psu : Thermaltake smart rgb 700watt
sound card : creative titanium fatality (the card is pciex1 plugged in the pciex1)
wifi & blue tooth : TP link TX300E (the card is pciex1 plugged in the pciex4)
with 1 NVME+1sata ssd and 3 internal hdd
the air flow is quite good, cpu when idle is around 45c, GPU when idle is 35c

the problem first starts a year ago when i add NVME to the mobo, some of my external hdd keeps disconecting and crash (which i plug in all the time with no problem when i use sata sdd). when it crash, the mobo LED light keeps ON even when i force it to shut down. it wont get back to "normal" if i dont cut off the power supply power. so i made compromise with that and un plug what i didnt use.

fast forward to 1 month ago, i updated to win 11, everything looks ok.
but then a week later i got random monitor signal lost. (when i play video, the display is lost but the sound is still playing, and then i have to force shut down)
after i force shutdown, the mobo LED keeps ON, the LED only turns off after i cut power to power supply.
when i turn on the PC gain, sometimes it starts up perfectly (1 short beep),
sometimes it gave me (1long 3 shortbeep, which is for AGP eror in gigabyte website) then i have to cut the power off and wait for 10 seconds to power it again
most of the time the windows automaticly disable the GPU, which i have to enable the GPU in "manage - device manager"
it happens randomly, it did not happen with some specific scenario. i tought it was windows 11

but just now i clean install the system with win 10
and it happen 1 time before i write this thread.

anybd experined the before?
thanks for the reply


Jan 14, 2010
AGP is a long-lost (in the annals of tech) interface. That should have no application here.

Do you mean GPU failure?

i dont know if it is GPU failure or mobo's pciex failure.
since the first problem starts with mobo stability when i changed sata ssd to nvme and being plugged too much usb external hdd