I have this Mobo https://www.gigabyte.com/uk/Motherboard/B450-I-AORUS-PRO-WIFI-rev-10/support#support-doc Which has only 2 Dimm Slots The QVL list I downloaded has a number of 3600 Mhz kits listed and when googled they seem to be 4 dimm kits (for the 32 gb kits) QVL List: https://download.gigabyte.com/FileList/Memory/mb_manual_b450-i-aorus-pro-wifi_matisse.pdf Am I a dunce or are they seriously recommending that 4 DIMM kits are compatible with a 2 DIMM mobo!
I think they are saying that you could take two sticks from one of the 4x16GB kits and use those? The sticks should be identical between the 2x and 4x kits...
Yeh, its just a Qualified Vendors List, so just 'we've validated that these will work on the board', not that you'll be able to use the whole set, that'd be a compatibility list
Nah, as someone who does this kind of testing for my ccompany it'll be 'get one part used in multiple kits, test part, sign off, sign off on all kits with that part'. It'll be management wanting to fluff the numbers to look better.
That's a few hundred to thousand variants (even excluding kits that use the same sticks with different labels or heatsinks) just for one speed rating, likely enough to violate the insertion count limit of the DIMM slot mechanism just from testing! Then there's the time needed to validate all of them, at maybe a 10 hours of testing per DIMM and 10 operators (a big QA department just for one board under test) that could be several weeks just waiting on DIMM evaluation! Whoops, gotta tweak the board, time to do add another few weeks to the production cycle!
They'll test one DIMM of a series, probably the highest speed one, and validate that, then probably run a script that'd cycle through validating different clock speeds, so one test machine can perform hundreds of tests without a person doing anything. That's how I'd do it with my systems. Otherwise its far to big a time/money sink and no company wants to just wasting money as thats when the shareholders start asking questions Plus with board there will be common designs then all other designs are derived from that annd testing is assumed to be valid as the underlying design is the same. That 2 DIMM board will be exactly the same as a 4 DIMM one, only that'll do the 4DIMM one first then just delete the extra 2 sections now needed, as well as the extra power. Then the testing is applied to the 4 DIMM one but carried over to the 2 DIMM version as they're basically the same
The answer is in the link name. It says "Matisse". The QVL memory list is something done on CPUs, because the memory controller is on the CPU. So they didn't test that specific RAM on that specific board, they just tested it on that CPU. I only realised this a couple of days ago, when a forumite was having stability issues on another forum. His RAM was on the QVL, but for some reason it appeared the RAM was dead. It was 3600 16 something, IIRC. Any way, I suggested he relax the timings to 18 (which every one told me I was wrong about and that it was dead memory or PSU etc) and it turns out that fixed it. When he looked closer he realised that yes, his RAM was on the QVL but only running 18 timings lol. I'm sure I read that the QVL comes from AMD, btw, not the board manus.
Makes sense if the memory controller is on the CPU. However a common sense approach from gigabyte would have just deleted any 4DIMM sets from the list. Unless of course I just buy a 4 DIMM set and toss the spares