By: Sam G (samg.delete@this.gmail.com), June 22, 2022 12:06 am
Room: Moderated Discussions
> > There is no mention of ECC in the Tech Specs section of the Mac Studio page on Apple’s website.
> ECC is problematic to provide with LPDDR.
Micron LPDDR4 and LPDDR4x DRAM includes on-die ECC:
micron.com/about/blog/2017/february/the-advantage-of-ecc-dram-in-smartphones
LPDDR5 has Link-ECC. Inline ECC can be used with both LPDDR4 and LPDDR5 as described here:
semiengineering.com/what-designers-need-to-know-about-error-correction-code-ecc-in-ddr-memories
> It may become more scarce in general with DDR5 since the bit overhead doubles
You’re right about an ECC DDR5 DIMM being 80 bits wide, compared to 72 bits wide for an ECC DDR4 DIMM. As you know, this is due to the DDR5 data bus being split into two subchannels. All DDR5 DRAMs, whether on an ECC DIMM or a non-ECC DIMM, have on-die ECC, which is an additional 6.25% overhead. DRAM sizes are increasing with DDR5 so ECC is more essential.
> ECC is problematic to provide with LPDDR.
Micron LPDDR4 and LPDDR4x DRAM includes on-die ECC:
micron.com/about/blog/2017/february/the-advantage-of-ecc-dram-in-smartphones
LPDDR5 has Link-ECC. Inline ECC can be used with both LPDDR4 and LPDDR5 as described here:
semiengineering.com/what-designers-need-to-know-about-error-correction-code-ecc-in-ddr-memories
> It may become more scarce in general with DDR5 since the bit overhead doubles
You’re right about an ECC DDR5 DIMM being 80 bits wide, compared to 72 bits wide for an ECC DDR4 DIMM. As you know, this is due to the DDR5 data bus being split into two subchannels. All DDR5 DRAMs, whether on an ECC DIMM or a non-ECC DIMM, have on-die ECC, which is an additional 6.25% overhead. DRAM sizes are increasing with DDR5 so ECC is more essential.
Topic | Posted By | Date |
---|---|---|
M2 benchmarks | - | 2022/06/15 12:27 PM |
You mean "absurd ARM"? ;-) (NT) | Rayla | 2022/06/15 02:18 PM |
It has PPC heritage :) (NT) | anon2 | 2022/06/15 02:55 PM |
Performance per clock | — | 2022/06/15 03:05 PM |
Performance per single clock cycle | hobold | 2022/06/16 05:12 AM |
Performance per single clock cycle | dmcq | 2022/06/16 06:59 AM |
Performance per single clock cycle | hobold | 2022/06/16 07:42 AM |
Performance per single clock cycle | Doug S | 2022/06/16 09:39 AM |
Performance per single clock cycle | hobold | 2022/06/16 12:36 PM |
More like cascaded ALUs | Paul A. Clayton | 2022/06/16 01:13 PM |
SuperSPARC ALU | Mark Roulo | 2022/06/16 01:57 PM |
LEA | Brett | 2022/06/16 02:52 PM |
M2 benchmarks | DaveC | 2022/06/15 03:31 PM |
M2 benchmarks | anon2 | 2022/06/15 05:06 PM |
M2 benchmarks | — | 2022/06/15 07:21 PM |
M2 benchmarks | --- | 2022/06/15 07:33 PM |
M2 benchmarks | Adrian | 2022/06/15 10:11 PM |
M2 benchmarks | Eric Fink | 2022/06/16 12:07 AM |
M2 benchmarks | Adrian | 2022/06/16 02:09 AM |
M2 benchmarks | Eric Fink | 2022/06/16 05:46 AM |
M2 benchmarks | Adrian | 2022/06/16 09:27 AM |
M2 benchmarks | --- | 2022/06/16 10:08 AM |
M2 benchmarks | Adrian | 2022/06/16 11:43 AM |
M2 benchmarks | Dummond D. Slow | 2022/06/16 01:03 PM |
M2 benchmarks | Adrian | 2022/06/17 03:34 AM |
M2 benchmarks | Dummond D. Slow | 2022/06/17 07:35 AM |
M2 benchmarks | none | 2022/06/16 10:14 AM |
M2 benchmarks | Adrian | 2022/06/16 12:44 PM |
M2 benchmarks | Eric Fink | 2022/06/17 02:05 AM |
M2 benchmarks | Anon | 2022/06/16 06:28 AM |
M2 benchmarks => MT | Adrian | 2022/06/16 11:04 AM |
M2 benchmarks => MT | Anon | 2022/06/18 02:38 AM |
M2 benchmarks => MT | Adrian | 2022/06/18 03:25 AM |
M2 benchmarks => MT | --- | 2022/06/18 10:14 AM |
M2 benchmarks | Doug S | 2022/06/16 09:49 AM |
M2 Pro at 3nm | Eric Fink | 2022/06/17 02:51 AM |
M2 benchmarks | Sean M | 2022/06/16 01:00 AM |
M2 benchmarks | Doug S | 2022/06/16 09:56 AM |
M2 benchmarks | joema | 2022/06/16 01:28 PM |
M2 benchmarks | Sean M | 2022/06/16 02:53 PM |
M2 benchmarks | Doug S | 2022/06/16 09:19 PM |
M2 benchmarks | Doug S | 2022/06/16 09:21 PM |
M2 benchmarks | --- | 2022/06/16 10:53 PM |
M2 benchmarks | Doug S | 2022/06/17 12:37 AM |
Apple’s STEM Ambitions | Sean M | 2022/06/17 04:18 AM |
Apple’s STEM Ambitions | --- | 2022/06/17 09:33 AM |
Mac Pro with Nvidia H100 | Tony Wu | 2022/06/17 06:37 PM |
Mac Pro with Nvidia H100 | Doug S | 2022/06/17 10:37 PM |
Mac Pro with Nvidia H100 | Tony Wu | 2022/06/18 06:49 AM |
Mac Pro with Nvidia H100 | Dan Fay | 2022/06/18 07:40 AM |
Mac Pro with Nvidia H100 | Anon4 | 2022/06/20 09:04 AM |
Mac Pro with Nvidia H100 | Simon Farnsworth | 2022/06/20 10:09 AM |
Mac Pro with Nvidia H100 | Doug S | 2022/06/20 10:32 AM |
Mac Pro with Nvidia H100 | Simon Farnsworth | 2022/06/20 11:20 AM |
Mac Pro with Nvidia H100 | Anon4 | 2022/06/20 04:16 PM |
Mac Pro with Nvidia H100 | Doug S | 2022/06/20 10:19 AM |
Mac Pro with Nvidia H100 | me | 2022/06/18 07:17 AM |
Mac Pro with Nvidia H100 | Tony Wu | 2022/06/18 09:28 AM |
Mac Pro with Nvidia H100 | me | 2022/06/19 10:08 AM |
Mac Pro with Nvidia H100 | Dummond D. Slow | 2022/06/19 10:51 AM |
Mac Pro with Nvidia H100 | Elliott H | 2022/06/19 06:39 PM |
Mac Pro with Nvidia H100 | Doug S | 2022/06/19 06:16 PM |
Mac Pro with Nvidia H100 | --- | 2022/06/19 06:56 PM |
Mac Pro with Nvidia H100 | Sam G | 2022/06/19 11:00 PM |
Mac Pro with Nvidia H100 | --- | 2022/06/20 06:25 AM |
Mac Pro with Nvidia H100 | anon5 | 2022/06/20 08:41 AM |
Mac Pro with Nvidia H100 | Sam G | 2022/06/20 07:22 PM |
Mac Pro with Nvidia H100 | Sam G | 2022/06/20 07:13 PM |
Mac Pro with Nvidia H100 | Doug S | 2022/06/20 10:19 PM |
Mac Pro with Nvidia H100 | Sam G | 2022/06/22 12:06 AM |
Mac Pro with Nvidia H100 | Doug S | 2022/06/22 09:18 AM |
Mac Pro with Nvidia H100 | Doug S | 2022/06/20 10:38 AM |
Mac Pro with Nvidia H100 | Sam G | 2022/06/20 07:17 PM |
Mac Pro with Nvidia H100 | Dummond D. Slow | 2022/06/20 05:46 PM |
Apple’s STEM Ambitions | noko | 2022/06/17 07:32 PM |
Quick aside: huge pages also useful for nested page tables (virtualization) (NT) | Paul A. Clayton | 2022/06/18 06:28 AM |
Quick aside: huge pages also useful for nested page tables (virtualization) | --- | 2022/06/18 10:16 AM |
Not this nonsense again | Anon | 2022/06/16 03:06 PM |
Parallel video encoding | Wes Felter | 2022/06/16 04:57 PM |
Parallel video encoding | Dummond D. Slow | 2022/06/16 07:16 PM |
Parallel video encoding | Wes Felter | 2022/06/16 07:49 PM |
Parallel video encoding | --- | 2022/06/16 07:41 PM |
Parallel video encoding | Dummond D. Slow | 2022/06/16 10:08 PM |
Parallel video encoding | --- | 2022/06/16 11:03 PM |
Parallel video encoding | Dummond D. Slow | 2022/06/17 07:45 AM |
Not this nonsense again | joema | 2022/06/16 09:13 PM |
Not this nonsense again | --- | 2022/06/16 11:18 PM |
M2 benchmarks-DDR4 vs DDR5 | Per Hesselgren | 2022/06/16 01:09 AM |
M2 benchmarks-DDR4 vs DDR5 | Rayla | 2022/06/16 08:12 AM |
M2 benchmarks-DDR4 vs DDR5 | Doug S | 2022/06/16 09:58 AM |
M2 benchmarks-DDR4 vs DDR5 | Rayla | 2022/06/16 11:58 AM |