Question Faulty piece of RAM or bad assumption?

[telesien]

I have decided to upgrade RAM from 8GB to 16GB,
However my rather oldish MB Asus H170M-plus doesn't allow faster than 2133 Mhz, which is now pretty hard to get.

I found a cheap 16GB stick of 2666 MHz RAM and under the impression, that it will work when I will use it on its own installed it. First it booted just fine and in BIOS I saw that it was successfully recognized. However since I exited BIOS, PC stopped working (no signal goes to monitor, despite everything running).

Putting the old RAM back makes it work again. So did I screw up with the assumption or is it issue of faulty hardware?

 

[PC Tailor]

Does it work with the just the new modules and the old ones removed?
It could well be down to the mixing of the RAM modules, which is never guaranteed to work - it's a 50/50 bet.
Some older chipsets may struggle, but usually they just downclock the RAM. But it's not guaranteed to work.

 

[telesien]

No, I am not mixing them. I even placed the new one in the same slot as the old one.
Except from the different speed and size they are just the same. Both DDR4 HyperX Fury.

So you say that using faster RAM than MB allows sometimes work and sometimes doesn't?

 

[PC Tailor]

Correct, most cases it will simply downclock that RAM to the highest supportable speed/frequency.
Other times it will bluntly refuse to work with them.

Have you tried each of the new modules individually in the slot as per your motherboard?
Have you also reset CMOS?

 

[telesien]

So far I only tried one slot, I struggled a bit with the other three and I don't like using too much force. I can still try though.

Resetting CMOS feels like something I might regret doing, since I have no idea if I need to make the new setup manually or not

EDIT: ok, I tried the other slots and no change

 

[telesien]

And I also tried the CMOS reset. It made the PC again work long enough to enter BIOS, where I could again see that I indeed have 16GB of RAM downclocked to 2133 MHz, but after exiting the BIOS everything went bad again.

 

[Calvin7]

HyperX HX426C16FB/1 does not downclock below 2666MHz.

JEDEC/XMP TIMING PARAMETERS
• JEDEC/PnP: DDR4-2666 CL16-18-18 @1.2V
• XMP Profile #1: DDR4-2666 CL16-18-18 @1.2V
https://www.kingston.com/dataSheets/HX426C16FB_16.pdf

No additional timing parameters are shown in the Plug-N-Play (PnP) Timing Parameters section.

Problem seems to be your choice of memory.

 

[telesien]

Thank you both for your help. Luckily I can return it back to the shop with only minor additional costs for full refund.

Meanwhile I was able to find shop that still has some leftover Corsair Vengeance in the correct frequency and I already ordered them.

With a bit of luck I might get 24 GB out of it, which is not that bad, when a moment ago it looked like I might be forced to go for Corsair Value select or something called Goodram