Question Mismatched ram stick failure, faulty stick or bad user?

Oct 20, 2021
4
0
10
0
Sorry for the question but I have been reading articles all day and it has only made me more unsure. I would consider myself to be of moderate skill when it comes to building a pc but I know I'm getting old and a little out of date lol.

I had 2 kits installed, F4-3000C15D-32GVR and F4-3000C16D-16GISB with XMP on. I am wondering if 1 of my 16gbs sticks was faulty or was there an issue with mixing them.

The F4-3000C15D-32GVR are only a year old and I will be getting a replacement from the store (or a comparable kit if out of stock) so I am using 2x F4-3000C16D-16GISB while I wait.

Ram Specs

F4-3000C15D-32GVR F4-3000C16D-16GISB

Capacity: 32gb (2x16gb) Capacity: 16gb (2x8gb)
Speed: DDR4 3000mhz Speed: DDR4 3000mhz
CL 15 CL 16
Timing: 15-15-15-35 Timing: 16-18-18-38
Volts: 1.35v Volts: 1.2v



Pc Specifics
MOBO: Asus Z270-a
CPU: Intel i7-7700k
Ram Slot 1: 16 gbs
Ram Slot 2: 8 gbs
Ram Slot 3: 16 gbs failed stick
Ram Slot 4: 8bgs
GPU: GTX 1060 3gb

EDIT
Built this system to what it is stated in the specs above on Sept 20 2020, earliest sign of issue was around May 2021.
When i checked the event log a Kernal Power 41 error was given and from the information i was finding online, this was likly caused by a PSU failure.

After doing some more digging with the info from the bug report out of window reliability history, I was finding more ram related articles and decided to do use Memtest86.

Testing the sticks one by one I found that the stick that was in slot 3 had 7434 errors. I reinstalled all the sticks minus the known faulty one and had no errors in Memtest nor did I have any issues when stress testing.
 
Last edited:

Ralston18

Titan
Moderator
Go to the Asus website.

1) Find the applicable User Guide/Manual for your motherboard.

2) Also check the QVL (Qualified Vendor's List) for supported RAM.

I found the following User Guide/Manual:

https://dlcdnets.asus.com/pub/ASUS/mb/LGA1151/PRIME_Z270-A/E12294_PRIME_Z270-A_UM_V2_WEB.pdf

(Confirm that I found the applicable User Manual.)

Supported RAM is listed on Page ix. Note the QVL reference.

Supported RAM configurations and relevant notes are presented on Pages 1-5 and 1-6.
 

mamasan2000

Distinguished
Only 1 way to find out if the 1 stick was faulty. Testing only that stick installed. But yeah, mixing RAM with different timings and volts, very tricky. even manually setting everything. I don't think your mobo had a chance to try and figure it out.
Kits exist because those have been tested together. If you buy 2 kits, there are no guarantees it will even POST.
 

GaryM

Distinguished
Jun 17, 2008
16
1
18,515
0
Although you want the modules to run at XMP settings, all modules will run at the same speed, latency, and voltage. So in your case with differing profiles, no more than 2 sticks can run their XMP profile. This then raises the question, what are the actual settings being applied by the BIOS to all 4 sticks? Was the stick you identified as "failed" running at its rated voltage of 1.35v or did it fail because it was undervolted at 1.2v? And of course, other settings raise similar stability issues. This is a case where manual intervention or verification is required. Simply setting the BIOS to use the XMP profile forces the BIOS to choose among the two profiles, and it may not have chosen correctly.
 
Oct 20, 2021
4
0
10
0
Go to the Asus website.

1) Find the applicable User Guide/Manual for your motherboard.

2) Also check the QVL (Qualified Vendor's List) for supported RAM.

I found the following User Guide/Manual:

https://dlcdnets.asus.com/pub/ASUS/mb/LGA1151/PRIME_Z270-A/E12294_PRIME_Z270-A_UM_V2_WEB.pdf

(Confirm that I found the applicable User Manual.)

Supported RAM is listed on Page ix. Note the QVL reference.

Supported RAM configurations and relevant notes are presented on Pages 1-5 and 1-6.


Thank you for your response,

This is indeed the correct manual, I have a copy of it and this is where I started my reading.
 
Last edited:
Oct 20, 2021
4
0
10
0
Only 1 way to find out if the 1 stick was faulty. Testing only that stick installed. But yeah, mixing RAM with different timings and volts, very tricky. even manually setting everything. I don't think your mobo had a chance to try and figure it out.
Kits exist because those have been tested together. If you buy 2 kits, there are no guarantees it will even POST.

I can't believe I forgot to state how I figure things out.

I installed the 32gb kit just over a year ago but have been getting random and infrequent crashes for a few months (3 or 4 a month) l decided to actually do some testing. I tested each stick individually with Memtest. The process took awhile, shut down, ground, remove stick ect..... anyways got to the 3rd stick and boom 7434 error by the 5th test.
 
Oct 20, 2021
4
0
10
0
Although you want the modules to run at XMP settings, all modules will run at the same speed, latency, and voltage. So in your case with differing profiles, no more than 2 sticks can run their XMP profile. This then raises the question, what are the actual settings being applied by the BIOS to all 4 sticks? Was the stick you identified as "failed" running at its rated voltage of 1.35v or did it fail because it was undervolted at 1.2v? And of course, other settings raise similar stability issues. This is a case where manual intervention or verification is required. Simply setting the BIOS to use the XMP profile forces the BIOS to choose among the two profiles, and it may not have chosen correctly.

Thanks for the replay, you make a lot of interesting points.

Unfortunately I don't have the answers to you questions. Although I don't recall all the specifics I do remember that my ram was running 1.3v (from the bios) 15-15-15-35 (from NZXT). Now I know that doesn't help at all but I think the 16gbs were stepped up with maybe the 32gbs running low like a "meet in the middle"scenario.

I am quite curious now though, would like to check and post my finding If I get a chance to revert back to the faulty setup to pull the details befor I get a replacement.

Regarding the replacement however, with the item being out of stock I am currently being offered a "comparable kit", I am currently debating if I should ask for a 1.2v 16-18-18-38 kit instead of the 1.35v 15-15-15-35.


Anyways thanks again for you help.
 

ASK THE COMMUNITY

TRENDING THREADS