UNSTABLE RAM ON NEW BIOS 1503 (microcode 129) on APEX ENCORE/14900K

[borcio02]

Hi,

so I updated my MOBO to newest BIOS in beta version 1503 and started testing things.

I set everything the same as previously on old BIOS. In this case is it about RAM so I have Corsair Vengeance 7200 MHz.

So I am getting almost instant crash while testing RAM by y-cruncher (VST) and PRIME95 (LARGE FFTs).

Previously I could test it by hours without any issues.

After few attemps I found weird solution. Go to BIOS -> Disable DIMM FLEX and disable XMP TWEAKED -> Set only XMP 1 and 7200 MHz speed. After that no more crashes.

Previously I had enabled DIMM FLEX and XMP TWEAKED and everything was good for 8 months, even if I was updating to new version when was available.

Do you have same problem maybe?

MOBO: APEX ENCORE Z790

CPU: 14900K

RAM: CORSAIR VENGEANCE 7200 MHz CL34

[Reticule]

Since i updated i lost my 6ghz oc. New bios sucks. Same mobo as you... had no issues till now

[Reticule]

I have 14900ks, patriot ddr5 8200, geforce 4090 rtx just so you know the specs. Windows 11 constant bsod same settings as 1400 bios. Wish I never flashed it.. 

Are you stock or oc ? I was 6.1ghz all cores, 47x ecore. Now I am lucky if ill hit 6ghz and 45x ecore. 

[Exist2Resist]

Yeah I have the same issue, when I set the IMC and SA voltage on the new BIOS it fails to post. 

[Silent_Scone · Accepted solution]

Hi,

1. Don't use Prime95. There's no need to expose the CPU to this much current unnecessarily and it's not indicative of conventional workloads.

2. I've not personally noticed any change in stability on the Encore moving to 0x129, but it's not uncommon for new ME firmware or ucode to have an impact on stability on some CPUs. If XMP I is still stable then the stability margin can't be too different between builds. You can always tighten some of the subs manually and retest.

3. VCCSA seems to have some behavioural changes on certain CPUs according to reports since the beta went live. You should be able to dial this out.

[Exist2Resist]

XMP is stable on 1402 but not 1503. Mind you I had to set the IMC voltage manually as XMP would not work at all without me bumping this. 

VCCSA, I have had this at 1.249 for for the last 5 BIOS revisions and stable. All of a sudden my system won't even post. There is something not right there.
I guess this is why it's beta. I'll stick to 1402 for the time being. 

[Silent_Scone]

I don't think it being beta is of much consequence over it being a new ucode. As said, if XMP I is stable and XMP Tweaked isn't it sounds like an alignment issue possibly. RD keep some of the changes for this profile undisclosed (as said previously, some behavioural changes have already been observed with 0x129). You can always adjust some of the sub timings manually.

[Exist2Resist]

Here is a good breakdown of what is going on. 

https://youtu.be/dqyaiTUaH9A?

[abortoletto]

The video shows a BIOS of an Asrock motherboard 

[Silent_Scone]

That video is riddled with misconceptions and misunderstandings, really not much else to say. Anything you want to point out to me in particular, feel free and I will clear the information up for you. There's too much in there that's wrong and as it's using Asrock it's not directly relevant.