Windows 7 64-bit not recognizing all 4GB of Installed Memory

Hey there!
I’ve been doing a bit of digging on Google, and it seems I’m certainly not the first person to run into this particular headache 😬 but I’ve already exhausted just about every troubleshooting step I could find online, so if anyone feels like sticking with me through the details...

The Issue:
Installed Memory: 4.00 GB (3.12 GB usable)
Here is what I’ve tried so far:
1.running msconfig -> boot -> advanced options -> checking the "maximum memory" box
2.Looking for memory remapping in the BIOS—though I couldn't find an option by that name or anything even remotely similar 🤷

Motherboard: My MSI 945 P Neo5 supposedly supports up to 4GB of RAM according to the specs;
http://www.msi.com/product/mb/945P_N...-specification
BIOS version: Currently on v9.4. I noticed there is an upgrade available to v9.5, but the changelog only mentions "update CPU micro code." To be honest, I'm a little nervous about flashing the BIOS, especially since the description doesn't explicitly mention adding a memory remapping feature, which makes me hesitate
http://www.msi.com/support/mb/945P_Neo5.html#down-bios
Processor: Intel Core2 duo CPU E4500 @ 2.2GHz—my research suggests this should handle 4GB of RAM just fine
Graphics Card: Nvidia GeForce 8600 gt

THE ONLY POTENTIAL CULPRIT:
I recently picked up an extra 2GB of RAM, but since I couldn't track down any modules running at the 400/533/667MHz speeds my motherboard officially supports, I ended up grabbing some 800MHz sticks from Amazon instead. The guy at the store assured me they would work perfectly fine together, but so far, no luck. I even tried swapping the positions of the sticks in the slots to see if that would trigger anything, but it didn't change a thing...

Did you make sure the memory was seated properly in the slots? I remember when I upgraded from 4GB to 8GB of RAM, my system only recognized 4GB at first. Once I gave the module a good, firm push to make sure it was fully clicked in, everything worked perfectly.

Oh, I certainly did! Those little plastic "lock" switches on the sides of the memory card—the ones that slide up and down to secure everything—snapped right back into place without any drama at all 🤷

I don't think it's possible for the RAM to be seated incorrectly, because if it were, the system wouldn't recognize it at all—you can't really have it partially working where one part functions and the other just disappears. This feels like a hardware issue to me. From what I can gather, the motherboard supports up to 4 GB of 667 MHz memory. That being said, the way you're describing this makes me wonder if you're actually running a 32-bit version of Windows; are you absolutely certain you have the 64-bit version of Windows installed?

Good grief, I can't even deal with this mouse right now, 🤔 because honestly, when it comes to me, anything seems possible if you try hard enough 😬
screenshot;
View on imgur

It might just be something tucked away in your BIOS settings. Maybe try resetting everything back to the factory defaults? Also—take a quick look to see if the BIOS actually recognizes all 4GB there.

It’s a hardware issue, plain and simple—specifically with that 945 chipset on the motherboard. Since this is a budget-friendly board, the chipset just has built-in memory addressing limits. Even though the board claims to support 4 GB, you can't dump the whole 4 GB into the OS because a chunk of it is always being reserved for other system services and devices.
Because we're talking about a physical limitation here, an update CPU micro code or a BIOS update isn't going to fix anything; the problem isn't a software bug.

Here is the Intel data for this specific chipset:
http://www.intel.com/Assets/PDF/datasheet/307502.pdf

The solution? You'll probably need to pick up a new motherboard.

It’s such a shame 👎

I really want to say a massive thank you to everyone for all the help you've given me! 👍

lol.

Look, your memory is fine and your PC isn't broken.

If you're running integrated graphics, it’s just going to shave off a few measly megabytes from your total. It's really not a big deal, honestly. 🙂

Go into your BIOS and try enabling "memory hole remapping"

It looks like you might have missed the opening post 😉

So look, you’ve got 2x2GB in there, right? Honestly, it doesn't even matter if the RAM is technically faster than what your motherboard can actually handle—it'll just automatically throttle itself down to the maximum frequency the board supports.
Basically, Maria James94 already laid it all out for you perfectly.

I wasn't actually trying to second-guess what O'Neill wrote, because honestly, it would be pretty silly of me to go seeking advice on a topic I clearly don't grasp just to turn around and dismiss it with a "no, it's actually like this" attitude.

I was simply reflecting on the points made in the previous post.