RAM upgrade and bus speeds

[Dave Baker]

I definitely need more RAM, currently I have 16GB 2400mHz DDR4 but it is not really enough for rendering anything other than very short timelines. I plan to increase the RAM to 64GB, the motherboard maximum, by replacing it with 4X16GB new sticks. The board supports from 2133mHz to 4000+mHz DDR4. My question is, if I put in higher bus speed RAM, e. g. 3000mHz, am I likely to cause any problems? I'm not looking to overclock.The CPU is Intel Core i7 8700k - Up to 4.7 GHz [6 Cores, 12 Threads].

Thanks for any advice you can offer.

[Christopher Young]

The main things to consider with RAM.

What speed RAM can your motherboard support?
Is your RAM optimized correctly to run at it maximum rated speeds?

May be worth having a look at the following video to see if it can give you some pointers on how to get the max out of your RAM settings in BIOS. Helped me when building my last system.

Chris Young
Sydney

ASUS MAXIMUS X HERO - Overclocking Test and Guide 8700K (en) - YouTube

[Dave Baker]

Cheers Chris, some interesting stuff in that video.

Having looked my mobo up on their website, it seems to be able to handle RAM at over 5000mHz (not what it says in the manual). Does it mean that if I replace the current 2400mHz RAM with, say, 4000mHz RAM it should work with no problems?

I've just been running some render tests and they prove thay my RAM is filling up in certain circumstances and causing a system crash. I am running without a swap partition to prevent slowing down in similar circumstances, so it has to be more RAM.

FYI I'm rendering GoPro 2.7k (2704 x 1520) to ProRes Standard and some clips are over 320mbps.

[Christopher Young]

Dave

More RAM can always be helpful for sure, especially if you are not running a swap file. I'm finding though that with the OC'd 8700k system I can handle UHD 50p from the Phantom 4 Pro without having to transcode which is a time saver. If you are doing a lot of MP4 rendering then a lot of help comes from the amount of RAM you have on your graphics card. I'm running a GTX-1080Ti with 11GB of onboard RAM and on 4K MP4 renders it uses a fair whack of that. ProRes is more CPU and system RAM dependent so yes any increase in system RAM is going to help. I don't know what software you are running that is causing you to run out of RAM? Years back Premiere used to be very bad at this as it wasn't releasing the RAM fast enough and eventually your renders would hang when you ran out of RAM. Might be worth checking your RAM with a Leak Test to make sure there are no issues there. If you are on Windows an open source leak tester and info can be found here.

Windows Leaks Detector

If on Mac maybe someone else can chime in to help out here.

Running 4000 RAM if your mobo supports it shouldn't be a problem if the RAM speed is seen correctly in the BIOS. If you re-watch the video with particular attention from 05:19 onward you will see how he sets the RAM speed correctly. In the example he gives he has DDR4-3603 with timings of 16-16-16-36-1 but to the right you will see the RAM is only being seen at a frequency of 2133. Once he applies the XMP profile the RAM parameters are automatically set and can now be seen to be running at a frequency of 3600 which is correct.

On some mobos you actually have to enter the RAM timings manually in the BIOS. If you don't know the timings you have to go to the RAM manufacturers web site to find out what the timings are for your particular RAM sticks and enter those timings and apply them. Your RAM should then be running at its optimum speed. Good luck!

Chris Young

[Dave Baker]

Chris

Running 4000 RAM if your mobo supports it shouldn't be a problem if the RAM speed is seen correctly in the BIOS.

That's what I wanted to know. I won't necessarily get 4000 RAM and I may not even go up to 64GB, but I don't want to shell out for something that isn't likely to work or, come to that, half do the job. A 64GB RAM kit will cost from about £400 upwards, so I want to be sure.

I'm running Cinelerra Infinity, otherwise known as Cinelerra-GG 5.1, on Manjaro KDE Linux. Watching the system monitor while rendering I see the CPU always has at least one core at 100% and the others at various precentages as they swap over, with twelve traces it's quite pretty actually! The RAM trace usually hovers around 12 to 14GB, but I have some allocated to VirtualBox which doesn't help. Cinelerra is good at relinquishing RAM, the second a process stops, the trace drops close to zero.

Thanks for your help.

[Christopher Young]

No worries Squire!

Chris Young
Ex Beeb Bristol & London :)

[Dave Baker]

Ex Beeb huh?

By coincidence, many years ago I used to do work for them as a subcontractor at some of their local radio stations: Radios Suffolk, Essex, Kent (both Chatham and Canterbury studios) and Northampton. It's a small world as they say.

Then there's the other Chris from Oz, Chris Harding, we're honorary twins, sharing the same birthday and year. What are the odds of that happening, meeting on a forum?

[Christopher Young]

I'll tell you how small it is. I grew up in India and went to school there. A guy I knew who I never saw again after the age of 10 dropped out of my life with a change of schools. Years later in my 60's I was in transit to the UK and on a transit stop at Geneva airport. During that stop I went for leak. A guy stepped up to the next booth and said "Long time no see Chris!" I nearly fell into the trough. He was on the same plane and had recognized me. What are the odds of that!? I wouldn't want to be a criminal on the run that's for sure. Needles to say we had a great catch up chat :)

Chris Young

[Dave Baker]

Chris

I was going to let you have the last word, we could go on swapping tales for ages, but I thought it might be polite to tell you the results of your help.

I went the whole hog and installed 64GB of Corsair Vengeance DDR4 2666mHz RAM, so no overclocking. I thought why not, I have to open the thing up to install 32GB, so I may as well put the maximum in and have done with it. I did a test run by re-doing the job it was crashing on and it flew through, caught me by surprise actually! Now I'm looking forward to completing the project to see how much easier and/or faster it is.

Thanks again
Dave

[Christopher Young]

All good to hear squire!

Chris