Ram woes

[techguyone]

I have this PC ordered from PC Specialist just over a year ago, pertinent specs are here:

ASUS® ROG STRIX Z490-F GAMING (LGA1200, USB 3.2, CrossFireX/SLI) - ARGB Ready

16GB Corsair VENGEANCE RGB PRO DDR4 3200MHz (2 x 8GB)

I decided to upgrade to 32GB so I ordered from Corsair on Amazon two more sticks of 8 GB RAM same speed.

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This might be one for tech support
2 days ago I bought Corsair Vengeance RGB Pro RAM DDR4 3200 MHz (2x8GB, product number CMW16GX4M2C3200C16) from the Corsair store on Amazon UK
Once it arrived I put it in my computer along with my current RAM (2 individual sticks of 8GB RAM and product number CM4X8GD3200C16W4). When it is in the computer, it will refuse to POST and some of the fans will refuse to spin unless the CMOS is reset. In addition to this, the RAM and the power indicator won't light up as if the system is not entirely;y getting the full power draw. I have tried:
- Putting the known good RAM into every slot (1,2,3 and 4) which works fine
-Putting the new RAM into slots (slots 2 and 4 in this case) and it refused to work
-Putting the new RAM into the remaining slots (slots 1 and 3 in this case) and it refused to work
-Testing each stick induvidually in different slots (the original 2 worked but the 2 new ones didn't)
-Mixing old RAM and new RAM in varying slots (computer refused to POST)
-Testing JUST the new RAM (no POST)
-Sending the RAM back and getting a replacement twin pack from Corsair Amazon UK (the new one still didn't work)
I'm assuming at this point that the twin 8 GB pack despite being Corsair DDR4 3200 MHz Vengeance Pro RGB RAM is not compatible with my motherboard, that said, is there a different SKU I could try?
I'm struggling to understand why essentially the same RAM refuses to work
What is the difference between (original) CM4X8GD3200C16W4
and new CMW16GX4M2C3200C16

 

[SpyderTracks]

I have this PC ordered from PC Specialist just over a year ago, pertinent specs are here:

ASUS® ROG STRIX Z490-F GAMING (LGA1200, USB 3.2, CrossFireX/SLI) - ARGB Ready

16GB Corsair VENGEANCE RGB PRO DDR4 3200MHz (2 x 8GB)

I decided to upgrade to 32GB so I ordered from Corsair on Amazon two more sticks of 8 GB RAM same speed.

---

This might be one for tech support
2 days ago I bought Corsair Vengeance RGB Pro RAM DDR4 3200 MHz (2x8GB, product number CMW16GX4M2C3200C16) from the Corsair store on Amazon UK
Once it arrived I put it in my computer along with my current RAM (2 individual sticks of 8GB RAM and product number CM4X8GD3200C16W4). When it is in the computer, it will refuse to POST and some of the fans will refuse to spin unless the CMOS is reset. In addition to this, the RAM and the power indicator won't light up as if the system is not entirely;y getting the full power draw. I have tried:
- Putting the known good RAM into every slot (1,2,3 and 4) which works fine
-Putting the new RAM into slots (slots 2 and 4 in this case) and it refused to work
-Putting the new RAM into the remaining slots (slots 1 and 3 in this case) and it refused to work
-Testing each stick induvidually in different slots (the original 2 worked but the 2 new ones didn't)
-Mixing old RAM and new RAM in varying slots (computer refused to POST)
-Testing JUST the new RAM (no POST)
-Sending the RAM back and getting a replacement twin pack from Corsair Amazon UK (the new one still didn't work)
I'm assuming at this point that the twin 8 GB pack despite being Corsair DDR4 3200 MHz Vengeance Pro RGB RAM is not compatible with my motherboard, that said, is there a different SKU I could try?
I'm struggling to understand why essentially the same RAM refuses to work
What is the difference between (original) CM4X8GD3200C16W4
and new CMW16GX4M2C3200C16

Firstly, what version of BIOS are you on? If it's an older version, there may well be an update to address RAM compatibility, they usually release a few in the following months after the boards release. It's possible an update would accommodate the new RAM.

RAM is very tricky, boards can be super picky about which DIMMS they're going to support, and it's more than just the speeds, it's the timings and voltages also.

 

[SpyderTracks]

On further investigation

The first DIMMS CM4X8GD3200C16W4 are the following specs: 1.35V, CL16-18-18-36

The second DIMMS CMW16GX4M2C3200C16 are the following: 1.2V, CL16-18-18-36

So primarily the voltage is the issue, they're not compatible. You wouldn't be able to run 2 different voltages, even if both pairs booted fine on their own.

 

[NoddyPirate]

On further investigation

The first DIMMS CM4X8GD3200C16W4 are the following specs: 1.35V, CL16-18-18-36

The second DIMMS CMW16GX4M2C3200C16 are the following: 1.2V, CL16-18-18-36

So primarily the voltage is the issue, they're not compatible. You wouldn't be able to run 2 different voltages, even if both pairs booted fine

The standard DDR4 voltage is 1.2V. Enabling XMP or DOCP raises that voltage to the more typical 1.35V in order to allow it achieve stability at the rated speed on the box. The second set above is shown this way by Corsair themselves - base reference voltage of 1.2V but tested up to 1.35V and it is only at that higher voltage that the latency values quoted can be achieved (they are 15-15-15-36 at 1.2V with 2133 MHz).

Corsair RGB Ram

There's no doubt compatability of some sort is the problem or less likely even just dead sticks, but it wouldn't appear to be voltage related.

(edit - image below confirming the latter RAM is also 1.35V at the rated speed and latencies......)

 

[techguyone]

We actually tried 4 sticks over two days, I can't see all 4 sticks being wonky, the bios is about 10 months old, update notes don't mention any changes to memory.

Regarding incompatibility, for 'bloke on the street' who has 'Corsair RGB Pro Vengeance RAM at 3200MHz, and then goes and buys Corsair RGB Pro Vengeance RAM at 3200MHz from the Corsair store at Amazon, you'd expect it to 'just work'

That aside, if anyone knowledgable here can find the original RAm (2 x 8 GB ) CM4X8GD3200C16W4 I'd happily give it a whirl, Google shows me one site, and it's out of stock indicating that perhaps it's an older version now discontinued.

Toms hardware has a post with something similar, but not quite the same, but it involved the same model numbers of RAM

[SOLVED] - Question pc reboots when i installed new ram, please help?

Hi so i bought a pre build system from cyber power and everything is running fine, basically i installed another two sticks of ram from amazon. As I found myself needing more than 16gb’s. The original ram in it is listed a 16GB (2x8GB) DDR4/3200mhz Dual Channel Memory (Corsair Vengeance Pro RGB...

forums.tomshardware.com

Amazon also have a 'this is a newer model' on the Vengeance Pro page, albeit 'optimised for AMD' with the code of CMH16GX4M2Z3200C16 wonder if this is worth a shot, although my CPU is Intel.

 

[NoddyPirate]

RAM timings and settings involve a large number of variables - literally dozens of settings within BIOS. If XMP is enabled it loads all these specs from the info held on the RAM DIMM itself and adjusts everything accordingly. I'd wonder if the suite of settings from your original RAM just don't quite work with the new sticks perhaps, even if the advertised primary timings (the four numbers you always see such as 16-18-18-36) are the same? Wild guess mind you, but that's the issue with RAM - even buying exactly the same RAM with identical part numbers and specs can sometimes still cause issues with pre-existing sticks. They're just finnicky things sometimes.

Do you know if XMP is enabled within your BIOS?

 

[techguyone]

We removed the CMOS battery to reset, as initially upon entering the new RAM only 2 of the fans out of 4 would light up and turn (besides the PC not even going to POST), doing this got all the fans to run correctly but still no POST, so no, XMP is off.

 

[NoddyPirate]

Sorry to say I can't say antyhing more than there being some incompatability of some sort hiding in the background. You can get your original RAM on aliexpress or ebay without too much trouble I think if you wanted to give that a shot:

Original RAM

Good luck!