4 of 8GB RAM missing

[Kaarel_K]

Hi

I am having some issues with my PC. Sometimes it boots with all the installed 8GB available, sometimes the resource monitor shows that 4 is available and 4 is hardware reserved.
It is weird since any boot up will either sometimes cause the issue, remove it or do nothing. Most days I need to run a reboot or 2 to have access to full RAM.
BTW My brothers PC seems to have the same problem which I cannot solve.

My specs:
CPU: AMD FX-8320
RAM: 2x4GB corsair vengeance
GPU: Gygabyte R9 280X
Motherboard: ASUS M5A97 LE R2.0
OS: Windows 8.1

Built it myself.
Bios has been updated, tried other RAM slots, ran memtest.

 

[Tradesman1]

Try raising the CPU/NB voltage about + 0.075 (i.e. if currently at 1.15 raise to 1.225)

 

[Kaarel_K]

Hey

Good quess but it didnt help. BIOS show always 8GB but windows shows 3,9GB. And yes i have 64 bit OS.

 

[Tradesman1]

Check in MSconfig that it isn't limiting the DRAM

START > type MSCONFIG in the search box > BOOT > ADVANCED > make sure max mem isn't checked

 

[Kaarel_K]

It is not, also since restart seems to fix this issue until I shut it down again, I suspect it might not be a windows settings issue. I also tried to lower the clock speed to 1333, but today it started up with 3,9 GB again.
I thought I knew a thing or two about computers but man this is driving me crazy.

 

[Tradesman1]

Are the sticks in slots 1-3 or 2-4, whatever the combo, trythe other combo, also what CPU cooler are you using?

 

[Kaarel_K]

Cooler master 212 evo. Using slots 2 and 4. Can´t use other slots as they are blocked by the cooler.

 

[Tradesman1]

Might try loosening the EVO then snugging back dow, quite often people overtighten one side or a corner which can throw the CPU out of level and it can affect the CPUs MC (memory controller)

 

[Kaarel_K]

Hey

Sorry for the pauses between posts, it takes time to properly test this out.
The issue has become less frequent. Missing RAM only happens when booting from shutdown(and not always anymore). Restart boot seems to be OK 100% of the time. I quess i can live with that unless you have any more good ideas.
Thanks anyway.

 

[Tradesman1]

Can try raising DRAM to 1.56 and CPU/NB another + 0.05 - also what PSU?

 

[Kaarel_K]

Will try raising.
PSU is Corsair CX750M. I know its a bit overkill on the wattage but hey it was on sale.

 

[Tradesman1]

It is a bit and should be fine, but the CX models use weak caps, if you have another PSU or can borrow one, might try that

 

[Kaarel_K]

After raising the voltage and booting the PC multiple times, I haven´t detected any more problems.

I think it was a combination of CPU cooling position and RAM voltage that did it.

Thank you for your help.

 

[Tradesman1]

No worries, glad all is well, that's the biggie