[SOLVED] Installed new memory PC will not boot.

[DE3187]

Hey all,

I've read a few threads here for some help and none of them fixed my issue.

Installed new RAM and my computer will not boot. Fans boots, GPU starts, but then my PC goes into a never ending loop of turning on and shutting off. I currently have my RAM (see below) installed in DIMM B1 & B2. I put the new RAM (which is the exact same model) into DIMM A1 & A2 (for a total of 4 DIMMS 32gb) PC won't boot. I tried putting just the new RAM in B1 & B2 and PC loads fine. Putting any combination New or Old RAM in slots A1 & A2 the PC will not boot. I've done the CMOS Jumper reset method & Removed the battery + Jumper reset method as stated in my mother board's manual, does not help. I've ran the Crucial System scanner and it states the max RAM is 32gb, so I'm not going over.

Here are my specs:
Operating System: Windows 10 Home 64-bit
CPU: Intel Core i7 4790 @ 3.60GHz
RAM: Corsair CMZ16GX3M2A1600C10 Vengeance 16GB (2x8GB) DDR3 1600 MHz (PC3 12800) Desktop Memory 1.5V
Motherboard: ASUSTeK COMPUTER INC. Z97-A (SOCKET 1150) (https://www.asus.com/us/Motherboards/Z97A/helpdesk_manual/)
Graphics: 4095MB NVIDIA GeForce GTX 980 (NVIDIA)
Storage: 232GB Samsung SSD 850 EVO 250GB (SATA (SSD)) & 2794GB Western Digital WDC WD30EZRZ-00GXCB0 (SATA)
Optical Drives: ASUS DRW-24B1ST a

Thanks in advance!

 

[PC Tailor]

Hi DE3187, welcome to the forums!

Yes your CPU and MB supports the RAM you are installing as well as the size and type, but:

Mixed RAM modules are not guaranteed to work together. They are sold in the form sold, and the modules in one pack are the only ones guaranteed to work together. This is irrespective of whether they are the same model / timings / type. RAM manufacturers do not support mixed RAM modules even of the same model.

It's always best practice when upgrading RAM to buy a whole new pack.

 

[DE3187]

Hi DE3187, welcome to the forums!

Yes your CPU and MB supports the RAM you are installing as well as the size and type, but:

Mixed RAM modules are not guaranteed to work together. They are sold in the form sold, and the modules in one pack are the only ones guaranteed to work together. This is irrespective of whether they are the same model / timings / type. RAM manufacturers do not support mixed RAM modules even of the same model.

It's always best practice when upgrading RAM to buy a whole new pack.

I did buy a brand new pack. The manual says that you can install a combo varying types of RAM. The new RAM works in slots B1 & B2 same as the old RAM. It’s when I put anything into slot A1 or A2.

My MEMok! Light is flashing which does not indicate any errors and I even pressed it but that didn’t work.

 

[PC Tailor]

I did buy a brand new pack.

I mean that whatever RAM you want to use for your computer, you should buy the whole new pack entirely. If you currently have 4GB and want 8GB, best practice is to buy a new pack of 8GB, not a new 4GB and add to your current.

The manual says that you can install a combo varying types of RAM.

The manual does not state that you can install varying RAM, it says you can install various RAM sizes, as you can with nearly every board. But it also says:

"Always install DIMMs with the same CAS latency. For optimal compatibility, we recommend that you install memory modules of the same version or date code (D/C) from the same vendor."

This is because even the exact same model module from the same vendor can be manufactured differently over time, so the version and date code should match as this indicates that the modules have been manufactured in the exact same way and therefore should be compatible.

Don't get me wrong, I'm not saying mixing RAM modules is never going to work, people do it plenty (as I have), but it's a 50/50 whether it will work, as memory manufacturers only guarantee compatibility in the form sold - I.e. in the same pack. I have had many instances where mixed modules work, but I have also had many instances where they don't. Which is why the boards won't say you can't mix, but tend to put in small text that indicates you should try and get the exact same version and DC.

My MEMok! Light is flashing which does not indicate any errors

This can still pass the quick debug but you can still have a compatibility conflict.

It’s when I put anything into slot A1 or A2.

Interesting, so if you put just the 1 RAM module into slot A1 or A2, reset CMOS, and leave the remaining 3 unpopulated, the PC does not boot?

 

[DE3187]

Interesting, so if you put just the 1 RAM module into slot A1 or A2, reset CMOS, and leave the remaining 3 unpopulated, the PC does not boot?

Correct. I tried 1 of each of my sticks solo in both A slots nothing happens. My pc will boot if I have 1 of the 4 in either B slot. And I can mix old and new RAM in the B slots and it boots fine.

I’m assuming the A slots are bad? I may have to chalk this up as a loss until I get a new mobo.

 

[PC Tailor]

In which case, firstly I would reseat your CPU cooler and ensure it isn't on too tight, pushing it on too tight can cause the DIMM slots to become unusable or not to work in Dual Channel.
During the reseating, it may be apt to closely check your CPU socket for any (even slightly) bent pins as this can also cause these issues.

 

[DE3187]

I will try this as soon as I can. Thanks for all of your help!

Edit: This worked! Reseated the cpu fan and it booted right up. Thank you!

 

[PC Tailor]

Great news, yeah sometimes too much pressure on the CPU / Socket can cause issues with the memory slots - it happens quite a lot believe it or not.

I'm glad you've got it fixed now, just remember to select best answer once you're happy my friend!