Word on the street is that the HyperX DIMMs used by Dell have slightly different SPD settings than the ones sold by Kingston to the general public.

Additionally, there's an inherent problem with the R7, R8, and possibly R9 boards that prevent the usage of 4x8GB DIMMs.  Stupid I know, but everyone's that tried using 4 matched 8GB sticks has run into POST issues. I doubt that you adding 2 more potentially unmatched sticks would be successful where others have failed.

If you want to bump system RAM up to 32 GB, the best course of action is to pull the 2x8GB DIMMs you have now, sell them or stick them in a drawer somewhere, and purchase 2x16GB HyperX 2933 sticks. That's what I ended up doing.  I bought a used pair of 2933 HyperX RAM modules with red heat spreaders from the Amazon warehouse for $120.  Popped them in after removing the OEM 2666 modules and haven't had a single issue. Been running XMP1 with a slight CPU overclock with no stability issues at all.

Thanks

Can you share your amazon link please ?

@amstel78 :

Additionally, there's an inherent problem with the R7, R8, and possibly R9 boards that prevent the usage of 4x8GB DIMMs.  Stupid I know, but everyone's that tried using 4 matched 8GB sticks has run into POST issues. I doubt that you adding 2 more potentially unmatched sticks would be successful where others have failed.

Ok, I must have missed this one. How about 4x16GB? Doesn't work? Or is that a totally different horror story?

@GTS81 4x16 GB DIMMS should work.  It was only 4x8 GB DIMMS that showed issues in the R7 and R8 machines.  Not sure about the R9.

@amstel78  Can you please post the amazon link so I can do the same?

Just bought  32GB DDR4 3200Mhz  for $120 bucks from amazon today and installed it right after getting it, works like a charm with my existing 16GB of 2666 Mhz, now I have 48 GB of ram!! simply plug and play

Is your computer running all 48GB at 2666MHz? Or is it able to do 3200MHz for 32GB and 2666MHz for the earlier 16GB?

Thank you for posting this. After many try’s and fails this configuration worked. Bought on amazon.  

This is ridiculous. I bought an R8 last year with 16G via two 8G sticks. I bought two more Dell certified 8G sticks that are OEM so I can upgrade. I get the same post issue. The manual says it can handle 8x4. I am running the latest bio version of 1.0.12. Does anyone from Dell acknowledge our concerns? These are not cheap boxes. Will it be fixed or did I just eat memory? Telling me to buy 2 16G sticks doesn't cut it. If anyone here can tell me a workaround it would be much appreciated. Dell, a rep responding to my query would be very beneficial.

Thank You.

Actually, if you read page 61 of the service manual, 8gb x 4 = 32gb is not listed as a supported configuration.  I know this makes no logical sense, but it was well documented / confirmed in this forum on the R7 that this is in fact not supported (which fyi the r7 also has that pegatron z370 board, just like the r8, only real difference is bios update).  I thought they had patched this by now via bios update for the r8. Why don't you try clearing CMOS?

Germanium,

Thank You for your response. This is bad architecture. The original document that I had said otherwise.

Thanks.

I purchased 2 8 gig sticks from crucial. Put them in the 2 remaining slots as my r8 shipped with 2 8 gig sticks. No issues at all.

Are you able to make all 4 sticks run at their maximum advertised frequency? For example if the Crucial memory is 3200MHz, do you see them running at that speed?

@cubicfang @r72019 :

R8's service manual always confuses me. It says to use Slot 1 and 2 if you need to install two memory modules. But the factory setup was using Slot 2 and 4 (both colored in black). I honestly don't know what slots I should use if I want to do some memory upgrade. 

This is a known documentation issue that has been feedback and acknowledged by Dell. Follow the colored tabs i.e. same colors fill up first.

@r72019 

R8's service manual always confuses me. It says to use Slot 1 and 2 if you need to install two memory modules. But the factory setup was using Slot 2 and 4 (both colored in black). I honestly don't know what slots I should use if I want to do some memory upgrade.