Technology

I had this exact issue a couple of years ago. Exactly the same problem: 16gb installed (and recognised by the BIOS), but Windows wouldn't use more than 8gb, even though it could detect its presence. And right now, I'm really annoyed with myself for not being able to remember what the fix was. It was... definitely something hardware-related, not software/configuration. I'm off to bed now, so if it comes to me overnight, I'll pop back in tomorrow.

Since what everyone else has suggested hasn't worked, there's 3 more things to test:

1. Update your BIOS. Depending on the age difference between your CPU and your MOBO, the BIOS might not be configured correctly for your CPU and thus half your RAM is unable to be addressed.

2. Test your RAM sticks and memory slots individually. Put your sticks in the primary channel (per your MOBO specs) one at a time and reboot to see if they're actually working. Then try moving them around to see if the issue is a bad slot, rather than a bad stick.

3. Are you sure you're not running a 32-bit OS? You'd be capped at 4GB system memory on 32-bit Windows, for example, no matter how much physical RAM you have.

Okay, I'm back and I have slept. Have a look at your CPU. I'm 90% sure that's where the problem was when I had this issue. I think in my case, one of the pins was slightly bent, and once it was very carefully straightened, the problem went away. But it could also be just not seated properly, or is overheating, or has dust on it.

msconfig has a maximum memory option. Worth checking that to make sure it’s not set to 8gb.

Could also be that you’ve installed the sticks in a weird configuration. Often if you have 4 slots the board actually wants you to populate slots 2 and 4 if you’re only using 2 sticks. Details are usually printed on the board.

Or could be reserve for the iGPU, have a look in the bios.

Once upon a time I read that this can happen when your CPU isn’t correctly seated but that always sounded weird to me so idk

I once had a TV tuner card use up 4GB of address space taking me from 8GB down to 4GB. Do you have any add-in cards that can be removed for testing? Or maybe any unnecessary onboard devices that can be disabled in the BIOS/firmware.

Update: I installed Linux and it's still not working I will tweak around with some of the settings yall suggested and get back to you ASAP. Also

No igpu Gpu: 1070ti ftw2 Ram: corsair vengeance pro ddr4 3600 I'll get my mobo soon im stepping out for groceries

I had this issue once on a PC a few years ago. I ended up having to slightly over volt the RAM in the bios. After doing that I no longer had any issues. By slightly I mean I upped it by the smallest increment once or twice.

Update: I stole my partners ram and put 4 x 8gb in there and now it's showing 16 GB available. Smh. So it seems something is reserving half of my ram. I reset bios to default. PLZ help lmaooooooooo

When did the issue start? Did you install new RAM? Are both the new sticks identical or of mixed make? A new CPU? Did you unseat and reseat the CPU or anything before this started?

You tried different RAM? Was it properly addressed or no? Did you try the current or different RAM stick by stick to verify each one is working on its own and then in the recommended slots as per your motherboard manual?

These steps/questions are necessary to determine whether the issue is a bad memory stick, something funky going on with the memory controller wrt slots, timings, combination of different modules, etc, or even the possibility of a defective memory controller or a bent/broken pin on the CPU.

I've had this happen on a system where it was either the chipset or the cpu that was unable to allocate more ram.

However that was an older system and I'm infamiliar with ryzen processors on this issue.

Only time I've ever had this happen, I had inadvertently over tightened my CPU cooler. Scythne ninja 2 was a godsend for small form factor builds, but damn it was easy to over tighten!

Unlikely, but your motherboard might have an extremely low max RAM capacity.

Search for your boards specifications and check how much RAM/Memory it can suppport. If you don't know your motherboards name, open CMD and type: "wmic baseboard get product"

Hey all still working on it I'll try a few more fixes today. Thank you guys so much for all the help 😭

Update: I updated bios and now I'm black screening so I'm kinda lost at this point. Should I just get a new PC at this point?

Do you have, and are you using, a dedicated graphics card?

If using the inbuilt GPU that's on your motherboard, windows will use system ram as GPU ram.

If that isnt the issue, can you tell us: windows version(s) you've tried, confirm all your ram sticks are same brand and size, and confirm if it's ever worked on this computer.

I know this might not be helpful.. but umm.. have you tried nit using windows?

Since the PC shows the full 16gb it must be registering it. So something inside windows must be occupying the rest of the space.

I've seen windows alone go up to 4+ GB so the ~8GB your missing here aren't unrealistic depending on what programs are running in the background.

What other hardware do you have installed in your system?

Can you take a screenshot of the Memory tab of Resource Manager?

It looks like the BIOS is reserving the memory for something. Reserving memory is pretty normal, but 8 GB isn't. Have you tried resetting your bios to default settings.

It is detecting your ram with what I can tell from the screenshot. What program is that anyways? But it a large portion is being used. I believe windows itself uses aroung 4gigs and you might just have programs in the background using the rest, even a web browser could use a decent chunk

What does task manager show?

how much is in your computer? just 16gb or is there more ?

I have a first-gen Ryzen with a similar issue (except I have 32GB of RAM but only 15.9 usable). Haven't found a fix in my case, but it seems motherboard-related, where an entire channel is detected but unusable. The only thing I haven't tried is swapping the board but that's probably my next step.