4 ms·

Having put together an i7-12900k rig on a z690 six months ago, two observations - * DDR5 is wildly different from previous generations in being much less stabl

by mapt 2y ago

Having put together an i7-12900k rig on a z690 six months ago, two observations - * DDR5 is wildly different from previous generations in being much less stable with more DIMMs, due to timing synchronization sensitivity. With four 6000 sticks I just flat out can't get more than a 12 hour stable prime95, even at jedec-4800 certified speeds. I can't even boot at 6000. My first few months were plagued with random crashes minutes into loading a game. * There is a consensus that we're operating at & beyond the limit of this consumer ATX platform's TDP. There are recognized limitations in the motherboard retention mechanism that has prompted the use of aftermarket shims. Only the very top of the line largest air heatsinks are practical, and even then you spend much of the time thermally limited. Daring people regularly prove that the heatspreader is a limiting factor by going back to bare die cooling and getting five or ten degrees of advantage. Because of the temp throttling becoming a normal state rather than an emergency protection, better cooling translates directly into higher performance. Intel 13th gen and 14th gen were supposedly very similar, with slight thermal improvements from the process node.

immibis 2y ago
I have an AMD Threadripper 7000 system with DDR5 ECC registered RAM, one stick per channel (maximum) and I've noticed that one corrected bit error is logged every few hours.
aspenmayer 2y ago
If you have memory errors, you can corrupt your OS during and/or after install time, which may explain some of your instability. Memory errors must be resolved prior to OS installation for any kind of expectations of problem-free usage.
- userbinator 2y ago
  An overnight run of memtest86+ with all the tests enabled (including the RowHammer ones) is necessary to verify RAM correctness. I wonder if the latter is related to this somehow.
  - aspenmayer 2y ago
    I would agree with your recommendations and your concerns. If you have RAM errors and proceed to install an OS, you’re gonna have a bad time. Windows SFC scans, DISM, etc can fix up some these issues after the fact, but unless you’re also going to repair-install all your software again, just save all the data and reinstall. It’s just not worth the trouble and you’ll be chasing your tail and ghosts forever.
wtallis 2y ago
> With four 6000 sticks I just flat out can't get more than a 12 hour stable prime95, even at jedec-4800 certified speeds. I can't even boot at 6000. Note that while your memory sticks may be rated to handle JEDEC's DDR5-4800 speed, and faster with XMP profiles, Intel's memory controller is only rated to operate at DDR5-4000 with two single-rank modules per channel, and DDR5-3600 with two dual-rank modules per channel. The speed of an individual DIMM is not the only important factor anymore. For the 12th gen parts, Intel didn't even promise DDR5-4800 unless the motherboard only had one slot per channel.
dboreham 2y ago
For desktop I'm on my second generation of AIO liquid cooling (as in, the machine I use now and the previous one three years ago are liquid cooled). Air cooling is too noisy.
Sohcahtoa82 2y ago
> Only the very top of the line largest air heatsinks are practical, and even then you spend much of the time thermally limited. Air cooling is just not adequate these days. For extreme CPU loads, it hasn't been adequate for YEARS. I've had an i9-9900K since about two months after its release, but had an air cooler on it. I'm a gamer, but nothing pushed all its cores until I got Cities: Skylines 2 last year. Even with my fan at 100%, I was bouncing off the thermal limit and getting a BSoD about once every hour or so. I had to turn down the thermal limit (and of course lose some performance, though I don't think I noticed) in order for my system to remain stable. Upgraded to liquid cooling, now I never go above 70C, and I could probably go even lower with a more aggressive fan profile. My wife did a system overhaul to a 13th gen i5, and we got a liquid cooler for her. She was like "I don't do crazy overclocking, why do I need a liquid cooler?", and I said that liquid cooling is basically a necessity for modern CPUs unless you're buying something low-end.

by mapt 2y ago

immibis 2y ago

I have an AMD Threadripper 7000 system with DDR5 ECC registered RAM, one stick per channel (maximum) and I've noticed that one corrected bit error is logged every few hours.

aspenmayer 2y ago

If you have memory errors, you can corrupt your OS during and/or after install time, which may explain some of your instability. Memory errors must be resolved prior to OS installation for any kind of expectations of problem-free usage.

userbinator 2y ago
An overnight run of memtest86+ with all the tests enabled (including the RowHammer ones) is necessary to verify RAM correctness. I wonder if the latter is related to this somehow.
- aspenmayer 2y ago
  I would agree with your recommendations and your concerns. If you have RAM errors and proceed to install an OS, you’re gonna have a bad time. Windows SFC scans, DISM, etc can fix up some these issues after the fact, but unless you’re also going to repair-install all your software again, just save all the data and reinstall. It’s just not worth the trouble and you’ll be chasing your tail and ghosts forever.

wtallis 2y ago

> With four 6000 sticks I just flat out can't get more than a 12 hour stable prime95, even at jedec-4800 certified speeds. I can't even boot at 6000. Note that while your memory sticks may be rated to handle JEDEC's DDR5-4800 speed, and faster with XMP profiles, Intel's memory controller is only rated to operate at DDR5-4000 with two single-rank modules per channel, and DDR5-3600 with two dual-rank modules per channel. The speed of an individual DIMM is not the only important factor anymore. For the 12th gen parts, Intel didn't even promise DDR5-4800 unless the motherboard only had one slot per channel.

dboreham 2y ago

For desktop I'm on my second generation of AIO liquid cooling (as in, the machine I use now and the previous one three years ago are liquid cooled). Air cooling is too noisy.

Sohcahtoa82 2y ago

> Only the very top of the line largest air heatsinks are practical, and even then you spend much of the time thermally limited. Air cooling is just not adequate these days. For extreme CPU loads, it hasn't been adequate for YEARS. I've had an i9-9900K since about two months after its release, but had an air cooler on it. I'm a gamer, but nothing pushed all its cores until I got Cities: Skylines 2 last year. Even with my fan at 100%, I was bouncing off the thermal limit and getting a BSoD about once every hour or so. I had to turn down the thermal limit (and of course lose some performance, though I don't think I noticed) in order for my system to remain stable. Upgraded to liquid cooling, now I never go above 70C, and I could probably go even lower with a more aggressive fan profile. My wife did a system overhaul to a 13th gen i5, and we got a liquid cooler for her. She was like "I don't do crazy overclocking, why do I need a liquid cooler?", and I said that liquid cooling is basically a necessity for modern CPUs unless you're buying something low-end.