AsRock Z77 Extreme4 - Random "memory not detected" error (55)


Junior Member
Aug 30, 2017
Hello everyone.Forgive me for the long post (TL:DR at the bottom).

I recently have been getting errors on my motherboard AsRock Z77 Extreme4 about memory not being recognized or detected, and I'm wondering if anyone here can help me resolve this issue as no matter how much I search through google the problem can't be solved.

Ok, I want to start by saying that a few hours ago I turned on my PC and was playing video games, browsing web etc... as I do everyday, no problems appeared or anything weird happening everything was normal. Then I noticed through GPU-Z that my GPU is running at x8 speed on PCIe Gen3 slot instead of x16 and heard it was better to make the GPU run always at x16, I realized it was because my GPU was mounted on a second PCIe 3.0 slot instead of the top one, so I decided to move it there.

Fast forward a few minutes of me putting my GPU at my top PCIe 3.0, and putting all cables back (PSU's GPU cables + DisplayPort) only to realize my PC won't turn on and when I look at AsRock's "Dr.Debug" LED troubleshooter, I see that the error I'm getting is "55, Memory not initialized". I really don't know why this is happening especially since I NEVER touched my RAM sticks while taking off/putting on my GPU.

It confuses me since seeing the PC was just working normally moments ago and now suddenly it can't recognize my memory ? To make matters worse, I removed my GPU from the case fully and wanted to try to turn on my PC with only onboard GPU only to get the same error as before.

That's pretty much it what my problem is , I also want to mention that I tried each stick in each slot separately only to get either "53, Memory not recognized" or "55, Memory not initialized", I'm pretty sure that my memory is fine seeing as how it worked all these years without any issues and just a few moments ago. If anyone faced this problem before help would be appreciated.

TL:DR: My memory suddenly can't get recognized by my motherboard, where just a few moments ago it was working fine (more detail above).

PC Specs:
CPU: i5 2500K @ 4.5GHz
GPU: MSI GTX 980 Ti Gaming
Motherboard: AsRock Z77 Extreme4
CPU Cooler: CM Hyper 212+
RAM: Patriot G2 8GB 1600MJz (2x4GB)
SSD: Samsung 850 EVO
HDD: Samsung Spinpoint 1TB HD103SJ
PSU: SuperFlower Leadex Gold 650W

Thanks in forward.