Can't use all my RAM in Windows

[DannyJ98]

Hey all, so I've got a Dell Precision T3500 tower (which I scored for free!) to replace my older PC. It's an X58 board, so it uses triple channel memory, so I've populated slots 1, 2 and 3 with 4GB DIMMs. However, it seems that Windows is only using 8GB, and has 4GB as 'hardware reserved'. I've tried looking online and following a couple of tips on how to fix it, but I've had no luck. Any help with this would be much appreciated please!

 

BIOS showing that the 3 DIMMs are detected:

 

Task Manager only showing 8GB as being used:

 

[svmlegacy]

Try reseating your ram, and using alternating slots.

(Pop, empty, pop, empty, pop, empty)

[DannyJ98]

Just now, svmlegacy said:

Try reseating your ram, and using alternating slots.

(Pop, empty, pop, empty, pop, empty)

Yep, that was the first thing I tried. It boots with each stick inserted by itself, and I've also tried one in all 6 slots to rule out one of the slots being faulty.

[Dango]

Run msconfig. In Boot tab, Advanced Options.. Make sure Maximum memory is unchecked. I

[DannyJ98]

Just now, Dango said:

Run msconfig. In Boot tab, Advanced Options.. Make sure Maximum memory is unchecked. I

I'm pretty sure I checked that earlier, but I just ran it again, and yeah, it's unchecked, with the number boxed greyed out with 0 in it. Is it worth checking it and setting it to 12288 at all?

[Dango]

Try run built-in diagnostic for memory. Make sure it pass for all of them.

[DannyJ98]

2 minutes ago, Dango said:

Try run built-in diagnostic for memory. Make sure it pass for all of them.

Good idea, I'll restart and give that a try.

[Dango]

Also check the iGPU reservation. I can't find T3500 BIOS manual to confirm it exists on Dell model tho.

[Guest]

Hi. I'm Shrimp. Bringer of bad news.

Either the Cpu dropped a channel or the Motherboard dropped a channel.

 

The only way to diagnose is with another cpu or another motherboard. 

 

I've had both occur. 

Cpu was FX-9590 with an HT link over 4ghz (stock 2.6ghz)

Killed the entire B channel. Done for. A cpu swap (I had several chips) determined it was the cpu.

This chip was de-lidded and then later given away at an OC comp.

 

The board was Z77 Extreme 4. It was known for dropping channel B. Would have symptoms as above described.

Only a new motherboard was the resolve. This issue over a broad variety of forums across many years is not new. Much more common than a cpu dropping a channel, but it's known to happen. 

 

Granted, none of my experiences with this issue was with a triple channel board, the principle still applies.

 

Easiest testing, swap the cpu.

Good luck.

[DannyJ98]

14 minutes ago, Dango said:

Also check the iGPU reservation. I can't find T3500 BIOS manual to confirm it exists on Dell model tho.

The memory diagnostic found no errors, and it's a Xeon so there's no iGPU.

[DannyJ98]

1 minute ago, ShrimpBrime said:

Hi. I'm Shrimp. Bringer of bad news.

Either the Cpu dropped a channel or the Motherboard dropped a channel.

 

The only way to diagnose is with another cpu or another motherboard. 

 

I've had both occur. 

Cpu was FX-9590 with an HT link over 4ghz (stock 2.6ghz)

Killed the entire B channel. Done for. A cpu swap (I had several chips) determined it was the cpu.

This chip was de-lidded and then later given away at an OC comp.

 

The board was Z77 Extreme 4. It was known for dropping channel B. Would have symptoms as above described.

Only a new motherboard was the resolve. This issue over a broad variety of forums across many years is not new. Much more common than a cpu dropping a channel, but it's known to happen. 

 

Granted, none of my experiences with this issue was with a triple channel board, the principle still applies.

 

Easiest testing, swap the cpu.

Good luck.

Yeah, I was worried that might be an issue, although I have tried all 6 slots and they work fine. I do plan on upgrading the CPU to a 6c/12t model though soon, so if it is the CPU for some reason, hopefully that fixes it.

[Dango]

Normally, Xeon end with 5 means it has iGPU. But I forgot it's pre-sandy. If CPU drop a channel, the memory won't be detected in the BIOS. The fact the OS can see there is total of 12GB means the memory is fully initialized. 

 

Here are couple things you can check.

• Look inside the BIOS, there may be a place that can lock the total amount memory. I see that with old Dell laptop before.
• Check the model number of the memories. Make sure they are identical. Dell sometimes really picky with different memory been installed.

[Guest]

Just now, DannyJ98 said:

Yeah, I was worried that might be an issue, although I have tried all 6 slots and they work fine. I do plan on upgrading the CPU to a 6c/12t model though soon, so if it is the CPU for some reason, hopefully that fixes it.

I'm a dummy. 

 

Carefully reading the OP. 

 

Quote

However, it seems that Windows is only using 8GB, and has 4GB as 'hardware reserved'

You actually don't have an issue. Ignore where it says memory usage 8GB. 
 

Pay attention to the available memory. You have plenty from 12GB considering the usage.

I'm a dummy. I should have carefully ready your original post more carefully.

 

You're good. 

[Guest]

8 minutes ago, Dango said:

Normally, Xeon end with 5 means it has iGPU. But I forgot it's pre-sandy. If CPU drop a channel, the memory won't be detected in the BIOS. The fact the OS can see there is total of 12GB means the memory is fully initialized. 

 

Here are couple things you can check.

• Look inside the BIOS, there may be a place that can lock the total amount memory. I see that with old Dell laptop before.
• Check the model number of the memories. Make sure they are identical. Dell sometimes really picky with different memory been installed.

On my Vega 3 it's called UMA buffer size or something goofy. (doubt it's the same on intel... shrugs)

[DannyJ98]

5 minutes ago, ShrimpBrime said:

I'm a dummy. 

 

Carefully reading the OP. 

 

You actually don't have an issue. Ignore where it says memory usage 8GB. 
 

Pay attention to the available memory. You have plenty from 12GB considering the usage.

I'm a dummy. I should have carefully ready your original post more carefully.

 

You're good. 

Are you sure? It's currently sat at 3.4GB used, with 4.5GB available, which adds up to 7.9GB.

[Guest]

Just now, DannyJ98 said:

Are you sure? It's currently sat at 3.4GB used, with 4.5GB available, which adds up to 7.9GB.

Mine says 14.9GB used from 16 available above it.

1.1gb reserved (am using iGPU) 

5.7gb is cached.

5 tabs open and only 10.9gb left to use in the system.

 

Now HW reserved could be a bad stick at worst I'm thinking.

Or like Dango said, the board is reserving the memory for something else. 

What that something else is, we are not sure of. 

 

So no I don't think anymore your cpu or board have an issue. I very much did not read your post slow enough. 

 

 

[Dango]

Here is something you can try too.

https://www.dell.com/community/Windows-General/Installed-RAM-16GB-only-4GB-in-BIOS-Precision-T5400/m-p/4050428#M356441

[Rooked]

Doesn't look like an issue to me.

[Dango]

BIOS update also worth a try.

[lazypc]

Just to echo my experience with what others have already said. Since you have been so thorough in troubleshooting already and ruled out iGPU reservation, and checked that each stick is good. I think your only recourse is to keep trying different slot configurations and stick orders to see if it detects it. As frustrating as it is to not have a concrete answer why, I have had a system in particular that was way too picky about RAM and slots.

Even though it's not recommended you could leave a stick in the first slot and test every other slot with a second stick to see if they are all working. Granted some mobos may throw a fit if you don't follow the every other slot rule.
I would also check if the BIOS has a way to specify Dual-Channel memory. Most mobos would auto detect this to enable, but worth a shot to look, and if dual channel is enabled somehow that would be the issue. Dual channel is only 2, 4, 6 sticks ect. 1, 3, 5 would go to single channel.

 

[lazypc]

And just to echo also that you are right in what you are seeing, when I have had issues with RAM being labeled as hardware reserved, that RAM is in fact unusable by the system, either reserved by iGPU or just unable to be utilized for a different reason.

[svmlegacy]

20 hours ago, ShrimpBrime said:

Or like Dango said, the board is reserving the memory for something else. 

What that something else is, we are not sure of. 

 

So no I don't think anymore your cpu or board have an issue. I very much did not read your post slow enough.

I've dealt with these boards before, and somehow, they can have a mind of their own for this. You were on the right path, for some reason or another, it'll disable a memory controller under "hardware reserved", essentially treating it as "untrusted". The memory will still show up in programs like HWiNFO, proving everything is talking to each other.

 

What can help, is manually setting the timings and speed in BIOS, and introducing one stick at a time. Sometimes you have to play with the order. Once they get all trained up, they're typically fine.

 

Here's what I would do:

1. Shutdown, clear CMOS
2. Install one single DIMM in Memory Controller A
3. Power up. Set as many timings and speed manually as possible.
4. Save, reboot into Memtest86.
5. Let run for a minute.
6. Power down, install a DIMM in Controller B
7. Boot up, verify in BIOS that the proper amount of memory is recognized.
8. repeat 4 & 5
9. Power down, install a DIMM in Controller C
10. See step 7.

If at some point, the memory does not show up properly, try swapping the sticks for each other, until it comes with all DIMM's enabled.

 

20 hours ago, lazypc said:

Just to echo my experience with what others have already said. Since you have been so thorough in troubleshooting already and ruled out iGPU reservation, and checked that each stick is good. I think your only recourse is to keep trying different slot configurations and stick orders to see if it detects it. As frustrating as it is to not have a concrete answer why, I have had a system in particular that was way too picky about RAM and slots.

Even though it's not recommended you could leave a stick in the first slot and test every other slot with a second stick to see if they are all working. Granted some mobos may throw a fit if you don't follow the every other slot rule.
I would also check if the BIOS has a way to specify Dual-Channel memory. Most mobos would auto detect this to enable, but worth a shot to look, and if dual channel is enabled somehow that would be the issue. Dual channel is only 2, 4, 6 sticks ect. 1, 3, 5 would go to single channel.

This platform as a whole does not support iGPU's, and additionally is not Dual-Channel. It is Triple-Channel. There is no option to enable/disable channels in BIOS.