Build Advice First RAM slot not working ECS H55H-M V1.1

[CausticCheeks75]

Okay so, (sorry for my bad english, it's not my first language) I have this very old secondary system with a really old motherboard and I wanted to upgrade it from 4gb RAM ddr3 (1x4 @ 1333MHz) to 8gb RAM (2x4). So I got matching RAM, same speed and all that stuff but I noticed that whenever I try to insert a memory module on the first slot (the one closest to the cpu), the pc refuses to post. Both ram sticks work, as I tried them both on the second slot and they worked fine, it only boots if that first ram slot is not populated. I've tried cleaning the slot, physically inspecting it (it looks fine), reseating the cpu and checking for bent pins or missing contact pads (there are none), using a different PSU, messing with bios settings, resetting the bios, etc... all to no avail.

If I boot into the bios by inserting just one stick on the second slot (the one that works), putting the ram in the first slot without exiting bios and then saving changes makes the bios say ddr3 dual channel and boot into windows. cpu-z shows two installed ram modules and hwinfo shows all the info about both modules but windows only shows 4 gigs. Restarting after doing all this results in no post again

So what should I do? is the cpu memory controller damaged? Or could it just be the motherboard slot

I apologize in advance if this is not the correct page in the forum for this type of questions
System:
ECS H55H-M V1.1
Intel Core i3-550

 

[helpstar]

Update the bios
Which exact memory models did you install?

Replace the bios battery

Please click the green human to continue - UserBenchmark

 

[CausticCheeks75]

Update the bios
Which exact memory models did you install?

Replace the bios battery

Please click the green human to continue - UserBenchmark

Thanks for your answer, I currently have the latest bios released for the mobo, should I reinstall it or something?

The old ram was a single Kingston ddr3 1333 MHz stick, and the ones I just bought are same specs but Samsung, I assume they're all compatible with the board since they all work on the second slot

 

[helpstar]

check the model name labeled on the Samsung 1333MHz modules

check the cpu socket pins of the motherboard if bent

did you replace the cmos battery yet?
if bios is up to date, that's ok then