Why Underclocking RAM ?

[davemon50]

In the timings table for RAM chips it lists several JEDEC specs for lower frequencies. Is there any reason why anyone would underclock their RAM? I have never read about people doing this, just wondering why you would, if there's some tangible benefit for some application. Any of you experts know the answer to this?

[Korth]

For troubleshooting the RAM, CPU, or motherboard. *A rarely needed capability, but vitally important when needed.

For increased compatibility. *Especially when using mixed RAM types, or different CPU/motherboard, or hardware with DMA to RAM. *JEDEC always guaranteed to work unless memory is faulty or misconfigured.

For boot, POST, EFI, etc, maximum reliability and stability when initializing hardware and firmware. *Maximum (and/or nonstandard) memory performance iis not needed before an OS is executed.
Power savings. *Admittedly very little power, but stretching (low) battery life or minimizing heat ouput can be important on mobile systems. *More important than a performance parameter which has little impact on many computing tasks.*

[davemon50]

Mixing RAM, that makes sense. Power savings does seem a poor solution, better savings elsewhere, but the mixing RAM does make sense. Looks like a quote, that yours? 🙂

[Korth]

Not a quote, lol. The text oddities are actually browser bugs I haven't figured out yet. Painstakingly typed that response while visiting the forums through a Chromium running on my nifty little ASUS Tinkerboard!

Don't discount hardware with DMA to RAM. This basically means (older) server-tech cards which occupy PCIe/PCI slots and have very strict (proprietary or kinda antiquated) RAM addressing/timing requirements - or cards installed through high-latency risers - these all tend to have their own executable firmware/BIOS which support interfacing to JEDECs and not much else.

I do like to be quoted. You can quote me on that. 😄