cancel
Showing results for 
Search instead for 
Did you mean: 

16 GB RAM - 8GB Usable

Azortharion
Level 7
This thread was originally about something else. Since I fixed that issue, another has cropped up where Windows considers one stick of 2x8 GB modules to be "Hardware Reserved", limiting me to 8 gigs of RAM. Other thread with same issue can be found here

Setup:

Ryzen 1700X
C6H, obviously.
CMK16GX4M2B3000C15 - Corsair - 16 gigs - 2x8GB, CAS15, 3000 MHz RAM.
BIOS: 1107 (latest beta as of writing)

When I boot, I get a RAM freq of 2133 MHz, which is default.

If I go to the BIOS and change the RAM frequency to anything that isn't 2133, the PC will boot, but it will stay at 2133 MHz in CPU-Z and the BIOS reading itself. This is even if I ask for 3200 MHz which shouldn't be bootable - it boots fine but stays at 2133 MHz.

The only way I can influence DRAM frequency is by changing the BCLK.

In the DRAM OC spreadsheet for this board, I have seen people achieve 2933 MHz with this exact kit.

The same applies if I manually try to put in CAS16 timings that I copied from the spreadsheet (16-17-17-17-36-1T), it boots fine but when I go in the BIOS, the actual timings are still the default CAS15.

This same problem happens with D.O.H.C profiles too.

Help, please? 🙂
9,574 Views
20 REPLIES 20

entropic-remnan
Level 9
Whenever the POST test goes through some memory stuff (like "memory training") it may not like the settings and will reset the memory timing to defaults. There are several things that can cause this and with these early BIOS's it's chore to figure out exactly what's going on but the later BIOS make it possible.

I have never made the "Doesn't Operate Computer Properly" (D.O.C.P.) setting work for me. I am running a 120 base clock and 32.5 CPU multiplier with a 2666 mhz memory speed. The result is a 3.9 ghz processor and 3200 mhz memory.

Few things to think about:

  • Voltages -- try setting the SOC voltage about 0.05 or .1 volts higher than stock. Verify and slightly overvolt your memory (I.E.: 1.35 volt memory to 1.4 volts)
  • Pre-boot voltage: in the Digi Power section of the Extreme Tweaker section, at the bottom, is a place to force the memory voltage higher when booting. Use the same value as your slightly boosted operating voltage.
  • ProcODT: This is under the advanced settings in the CBS section and you want the DRAM settings. In there (if you have a bios greater than 1002) is a setting for the termination impedance of the memory. Until I set mine to 68.8 (differs by memory brand) I couldn't get mine to boot into full speed reliably. You may have to play a bit to find the right value and you must test memory afterwards with something like HCI MemTest to verify that it's okay, even if it boots.


With these enhancements my 3200 mhz Corsair memory based on dual-rank Samsung E-dies actually boots up and stays at 3200 mhz.

Sorry it's not so simple, but think of the satisfaction you'll feel when you find the right numbers...
Tired of trolls and mods that act like this platform has no problems and it's the users fault. Later.

Hey man. I tried all 3 things you said:

Voltages:

1.4 (up from 1.35v) on both regular and the preboot (was called "VBoot" for me, assume it's the same thing?)
SOC voltage up to 1.1 (was there before, just neglected to mention)
Have set the impedance to 68.6 as suggested, and also tried 1 step above and below that so far. Worth noting that whenever I re-enter BIOS, this option has reset to "Auto", not sure if that is normal.

I am only trying to do 2400 MHz, nothing crazy. Mostly just to confirm that I can get something that isn't 2133. :S

Very open to further ideas, anxiously waiting for ASUS' proposed May BIOS update that should help some of these DRAM issues?

EDIT: After doing what you said, I appear to only have 8 gigs of RAM (it's a 2x8 kit). Also, all DIMM slots in the CPU-Z "SPD" tab are empty. I can just reset to get my 16 gigs back presumably, but this info might help troubleshoot the issue.

Well, you're not running to the end of my "expertise" such as it is, lol.

The reset of the ProcODT to "auto" means your memory didn't pass. When it fails self-test that's what happens. I presume you have the DIMM's in the same color slots, right? Some people miss that in the manual. They shouldn't be right next to each other, but in "every other slot".

Another thing is DON'T use 2400 timing. Set the timing to 2133 or 2666 only and skip the others. For some reason my Corsair Dominator Platinum 3200 doesn't like whatever those settings do. Then, if you want to go higher, tweak your Bclk up, and adjust your processor clock multiplier as needed. The only success I've had with my memory is on 2133 and 2666. In each case I still enter the off-the-package timings of 16-18-18-(18)-36 in the DRAM timings and don't let anything auto happen there either.

If you want to do 2400, select 2133 and tweak Bclk. No, changing Bclk is not ideal but most of the time these boards seem to work well into the 140 's on Bclk.

That's about all the advice I have to offer. All I know is what got me up and running. I'm sure as time goes on the board will get better and better. This is an improvement over the original 1002 BIOS I first flashed and my system is running as I hoped already -- everything else that comes is gravy. Oh, except getting my RGB LED's on the board working again. There's a problem a lot of us have where they just quit working.
Tired of trolls and mods that act like this platform has no problems and it's the users fault. Later.

entropic-remnants wrote:
Well, you're not running to the end of my "expertise" such as it is, lol.

The reset of the ProcODT to "auto" means your memory didn't pass. When it fails self-test that's what happens. I presume you have the DIMM's in the same color slots, right? Some people miss that in the manual. They shouldn't be right next to each other, but in "every other slot".



Sorry for interrupt ^^'' i agree with you about the slot position BUT if i put my two dimm on A2-B1 (so next to each other in the center) they run in dual channel, otherwise they're on single channel.

Huh. I was told otherwise. I'll give that a try and run some memory tests. Thanks!
Tired of trolls and mods that act like this platform has no problems and it's the users fault. Later.

So, I am stuck with 8 gigs of RAM even after reverting back to regular settings. But I had that issue on a previous BIOS and clearing CMOS and reinstalling the sticks seemed to help so I will try that.

Yes, the sticks are in the black slots (A1 and B1 I believe). When repopulating I will switch them to the grey ones I guess, as I assume it cannot hurt.

I'll try doing what you said with 2666 instead of 2400 and also manually putting timings (didn't do that before), although it auto-defaults to the correct timings on the package. Can't hurt. I will report back with an edit to this post soon enough.

Thanks so much for lending me your expertise here, it's a pretty gnarly issue as not much is known so I am very grateful that this forum has knowledgeable people like yourself helping scrubs like myself.

EDIT: So with your help, I got 2666 MHz working. Bad news is I still only got 8 gigs of RAM. CPU-Z SPD reads nothing for any slot. Seems I fix one issue and another crops up. 2933 MHz was still out of reach even at 1.4 voltage.

Ha ha! I laugh at being an expert, but thanks. Your real gratitude is to all the others here I gleaned this from. I too am new to this platform and the peculiarities of the early implementation. There are some real experts and experimenters here that have provided leadership to get us where we are and I'm grateful as well.

Is there anybody you could borrow a couple of sticks of RAM from? It would be nice to know if it's just a bad stick you got or if the motherboard has issues of some sort.
Tired of trolls and mods that act like this platform has no problems and it's the users fault. Later.

I do not have another DDR4 kit handy, but I guess I could buy new ones just to test, or something.

Interesting part is:

1) BIOS recognizes that there are 2 DRAM modules, and all the info pertaining to them. SPD info is full of stuff.
2) CPU-Z recognizes only 8 gigs of RAM, but it is in "dual channel" (thought that required 2 sticks?), the SPD tab is completely blank.
3) AIDA64 recognizes 2 sticks of RAM.
4) I have tested each DRAM module separately, and they both work (though if I do not CMOS reset when trying to use either one of them, I get an instant 0d Qcode that sticks). They individually give me 8 gigs of RAM, but together, they don't give 16, just 8.
5) Windows recognizes 16 gigs of RAM, but only 8 are usable.



Could it be a Windows issue at this point?

I flashed the new BIOS (1107, but not the beta version from the forum but rather the official one released today) but it did not fix the issue.

Wow, that's truly confusing. I'm stumped, sorry. I'll think about it but right now I can't think of anything else to add. Really weird that Windows sees 16 gigs of ram but tells you only 7.93 are usable. Maybe try each stick singly to see if one or the other is the "better" one? Maybe that might help identify a possible RAM issue.

Good luck -- hopefully someone pops in with something more for you.
Tired of trolls and mods that act like this platform has no problems and it's the users fault. Later.