Could incompatible RAM speed cause a MB to not Even Post?

[486DX Win3.1]

Could incompatible RAM speed cause a MB to not Even Post?  This is an older system.  New for me, just put it together today. 

 

AsRock Z170m  

i6600K 

2666 CL 16 Ram 

[BetteBalterZen]

Yes certainly. Do you have any POST LED indicators on the motherboard?

[Helpful Tech Witch]

30 minutes ago, BetteBalterZen said:

Yes certainly. Do you have any POST LED indicators on the motherboard?

yea... no
DDR4 RAM runs at a stock 2133 on any stick, any motherboard, specifically to not cause this

 

[486DX Win3.1]

27 minutes ago, BetteBalterZen said:

Yes certainly. Do you have any POST LED indicators on the motherboard?

ya know,.... it darn well says that there is a light on there somewhere, I mean a series of lights but for the life of me I can't find it. 

 

But I kind of answered my own question. I took my ram out of this PC (the one I am using now), which is CL 18 and 3600 Mh and I swapped it out with that darn oLo 2666Mhz and BOOM - I booted up to the Bios.  Turns out, Asus has a pretty solid bios user interface! I like it alot.  (I only used ONE 8 GB Stick)

 

 After that, I changed the advanced memory speed to 2666 and saved that setting in the bios, took my 3600 speed ram, put it back in my "maIN" rig, and now here I am writing this. 

 

 Question is - will the Bios keep the changes. 

[486DX Win3.1]

2 minutes ago, Helpful Tech Witch said:

yea... no
DDR4 RAM runs at a stock 2133 on any stick, any motherboard, specifically to not cause this

 

Reallllyyyyyy ????? I'm not so sure. Seems swapping some ram out with a different stick and then changing the speed MAY just do the trick.

[BetteBalterZen]

31 minutes ago, Helpful Tech Witch said:

yea... no
DDR4 RAM runs at a stock 2133 on any stick, any motherboard, specifically to not cause this

 

Ah yeah true, of course, I was a bit too fast there. Thanks for the correction. I think my thought came from knowing that some motherboards only support up to, lets say, 3200MHz and then if you installed 3600MHz, then that would not be compatible obviously, but of course, RAM are not locked that that speed and there's always JEDEC speeds. 

Sorry OP

[BetteBalterZen]

11 minutes ago, 486DX Win3.1 said:

 Question is - will the Bios keep the changes. 

The BIOS should detect RAM change and because of that do a memory retraining, and this should wipe previous RAM configurations

[486DX Win3.1]

18 minutes ago, BetteBalterZen said:

The BIOS should detect RAM change and because of that do a memory retraining, and this should wipe previous RAM configurations

Welp. No Dice. 

 

After saving the 2666 ram config in the bios, I put the oLo 2666 ram back in and tried to crank her up.... and - black screen again. 

 

It's a POSSIBILITY that because 2666 is not listed as a "supported" ram speed in the MB literature, that it just won't work. 

 

Only thing I can think to try is to disable XMP, set the MB to default ram speed which may very well be 2133, and see if it will boot up with the Crappy oLo ram at 2133 or whatever the MB default speed is. 

 

Otherwise, it just hates that RAM and I'll have to wait to get something else.

[BetteBalterZen]

Just now, 486DX Win3.1 said:

Welp. No Dice. 

 

After saving the 2666 ram config in the bios, I put the oLo 2666 ram back in and tried to crank her up.... and - black screen again. 

 

It's a POSSIBILITY that because 2666 is not listed as a "supported" ram speed in the MB literature, that it just won't work. 

 

Only thing I can think to try is to disable XMP, set the MB to default ram speed which may very well be 2133, and see if it will boot up with the Crappy oLo ram at 2133 or whatever the MB default speed is. 

 

Otherwise, it just hates that RAM and I'll have to wait to get something else.

Hmm, maybe take a look at the supported RAM speeds, maybe it is close to the 2666MHz. Then first reset BIOS, enable XMP and then manually change the MHz to whatever is supported by your motherboard which is closest to 2666MHz. Maybe give that a go

[DoctorNick]

1 hour ago, 486DX Win3.1 said:

Could incompatible RAM speed cause a MB to not Even Post?  This is an older system.  New for me, just put it together today. 

 

AsRock Z170m  

i6600K 

2666 CL 16 Ram 

 

i5-6600k supports 2133mhz without overclocking. You cant count on it working without tweeking. Did you enable XMP? Check if ram is in slot A2 and B2 on motherboard.

Try setting everything auto and then run aida64, go to motherboard->spd - find one of the sticks and take a photo of timings. Remember to expand the page, so you can see all the names of the timings in the right order. 

 

Example:

 

[Helpful Tech Witch]

On 8/12/2022 at 12:45 AM, 486DX Win3.1 said:

Reallllyyyyyy ????? I'm not so sure. Seems swapping some ram out with a different stick and then changing the speed MAY just do the trick.

yes.
thats how ram works, it will always run at the jdec 2133mhz until the XMP profile is enabled
If your having issues with ram speeds then clear cmos, that will make sure no prior enabled xmp profile is still trying to be applied