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Messages - pocock

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General Discussion / Re: Fractal Design cases
« on: October 08, 2020, 04:47:31 pm »

As discussed elsewhere, the PWM fan described here is now running at 1800 RPM.  The system is actually idle so this feels a bit odd.

It was 300 RPM when the system booted and it increased gradually over time.

From the perspective of the Fractal case, the default Fractal fans are rated for 1000 RPM.  Given a PWM fan, the system seems to prefer a lot more than 1000 RPM and that implies the default Fractal fans are not sufficient for a multi-CPU build like this.  They may still be suitable for somebody with single CPU, e.g. Talos II Lite with 4 or 8 core.

Mod Zone / is Talos II overclocking the fan?
« on: October 08, 2020, 04:42:59 pm »

ipmitool tells me that the PWM fan I put in the rear of my case is running at 1800 RPM

Noctua rates it for 1500 RPM +/- 10%, that suggests that 1650 RPM is the maximum

PWM, by definition, can't overclock or overvoltage anything, it simply increases the pulse width up to the point where pulses are 100%.  You can't PWM over 100%

Is the fan simply running outside the spec or could this be a reporting error?

General CPU Discussion / Re: POWER9 water cooling kit
« on: October 08, 2020, 03:44:06 pm »

At risk of going off-topic, I'd like to emphasize that water-cooling is only 50% of the problem when house-training the POWER9

The thread about powering-down unused cores is equally important

The CPU cores, especially in a dual-CPU configuration, using over 100W when idle, will waste electricity and generate unwanted heat.

Electric heating is particularly inefficient, 60-70% of electricity is lost in the energy network.  The only exception to this is the use of a local generator (renewable, cogeneration, etc), as it is generated locally, very little is lost in transmission lines.

In my own case, I'm using solar PV and the excess heat is therefore useful and efficient for 7-8 months of the year, it simply offsets the underfloor heating.

But for most people this could be expensive, wasteful and uncomfortable.

Solving both of these issues together (the water cooling and making some cores sleep when idle) will eliminate most concerns from buyers.

GPU Compute / Accelerators / Sapphire Pulse Radeon RX 550 4GB
« on: October 08, 2020, 03:20:49 pm »
The RX 580 was running fine but I don't use a lot of GPU so I decided to swap it for the Sapphire Pulse Radeon RX 550 4GB, it is half the price.

This card appears to be running fine too.

Monitoring it with the radeontop utility, I'm using 2.5GB of VRAM while driving two screens, one is 4K and the other is 1920x1200

As it is really cheap, I think this card is useful as a spare or for people who don't use GPU-intensive workloads.

The card is less than 2 PCIe slots width so it is an interesting choice for people who are using both slots on a Blackbird.

The sensors command tells me the fan is running at 1231 RPM idle, it is a bit faster than the fans on the RX 580.  I feel it may make just a little bit more noise compared to an idle RX 580 which has two fans that appear to be bigger and quieter.

I may decide to return this one as well and swap it for the Big Navi in November or maybe I will get a Big Navi and keep this as a spare.

My only real concern then is the fan noise, some people may want to pay that little bit more to get a more silent alternative.

General Discussion / Re: Fractal Design cases
« on: October 08, 2020, 03:02:58 pm »

I ran ipmitool and I didn't see any fan speed from the built-in fan hub of the Fractal case.

I decided to try replacing one of the default 3-pin case fans with a 4-pin PWM Noctua fan

If the fan is at the rear of the case, the 30cm cable from Noctua doesn't quite reach the fan connectors on the front of the motherboard.

The fan hub has some 4-pin connectors and 3-pin connectors.  It appears that it takes the speed sensor from the first 4-pin connector and passes that back to the motherboard.  Connecting the fan to the first 4-pin connector, I was able to see the speed with ipmitool.  I tried moving it to each of the 4-pin connectors and they all report 0, it only reports the speed if it is on the first connector.

Using the fan hub in this way also solves the 30cm problem because the fan hub is at the back of the case too.

At idle, I don't believe the system is significantly quieter using the Noctua fan.  ipmitool reports that the fan is running at its slowest speed, 300 RPM.  I suspect that any noise I can hear is coming from other parts of the system and not the Noctua fan.

Overall, it is convenient being able to see the fan speed like this but maybe I could see the fan speed by using a more advanced fan hub that can monitor the 3-pin case fans.

General CPU Discussion / Re: POWER9 water cooling kit
« on: October 07, 2020, 08:47:43 am »
I found the IBM HSFs quiet enough when idle as well, for everything else, like office or living room situations, those HSFs are unusable IMO.

I agree a lot of people will have trouble with the HSFs

Another thing that comes to my mind is the performance of the case fans: if somebody has some very large and quiet case fans, e.g. 140mm and they move a lot of air across the HSF will the motherboard fan logic be able to reduce the HSF speeds?

Looking at the Noctua fans, for example, they are offering fans with different maximum speeds, for example, 800, 1200, 1500, I even saw one with 3000.  They will be noisy as well but will the overall noise be lower?


For qtwebengine, it is very easy to enable ppc64el in the Debian control file but it won't work until it is enabled in QtWebEngine itself

As commented elsewhere, I was able to build OBS, I'll test it and make the packages available shortly.

A lot of interesting things depend on QtWebEngine

QtWebEngine depends on Chromium, they periodically take a snapshot of the Chromium code from Google

Chromium patching is already in progress, is it complete?

I opened a bug for it within QtWebEngine

When somebody confirms the Chrome patches are ready, the QtWebEngine developers could enable it in their list of supported platforms.  They will probably need to know the minimum supported version of the Chromium code, they probably won't have time to look through the Chromium history, if anybody could add comments to the Qt bug report that would be really helpful.

If they can cherry-pick patches that haven't been accepted by Google, please also comment on that Qt bug report

Talos II / Re: quiet rack mount cases e.g. water cooled or 5U, 140mm fans
« on: October 05, 2020, 04:29:11 pm »
Dune Pro is definitely an interesting alternative to the Fractal cases for tower users but it doesn't solve the rack problem in this thread.

In Switzerland, the building code says every house has to be built with a bunker.  People buy large rack mount UPSs, like the APC 1500VA or bigger and want to match them with something like Talos II in a small rack.  That is why I started this thread.  Sorry if I'm not able to idenify individual users but if you want to see the bunkers there are plenty of them, people who like hiking or motorbikes visit the mountain bunkers on weekends in summer.

Talos II / Re: quiet rack mount cases e.g. water cooled or 5U, 140mm fans
« on: October 05, 2020, 03:57:03 pm »
Many of the cases on that page have 120mm fans combined with some smaller fans.  I don't feel that will give the same quiet as a 140mm fan.

The only chassis with all 120mm appears to be a GPU mining chassis, it may be suitable but from the pictures it looks like the GPU slots obstruct the space for the POWER9 heatsinks

Talos II / quiet rack mount cases e.g. water cooled or 5U, 140mm fans
« on: October 05, 2020, 11:41:38 am »
I've had a few discussions with people about Talos II and Talos II Lite, mainly based on the recommendations in my recent blog post

One topic that comes up is that some people are space conscious and while the Fractal case is really nice and easy to use for this platform, you need to be able to access it from both sides because the HDDs / SSDs are under the motherboard and any case for the Talos II is going to be big anyway.

One of the ideas emerging from these discussions is building a small rack that can be positioned in the home or office like a chest of drawers or coffee table.  For example, such a rack could be shared between some engineers on a support desk.  A decent UPS can go in the bottom and the Talos II mounted in a large 5U case.  PDUs, network switches, etc can all be mounted on a shelf or rack mounted.  As it is not for data center, 4U to 6U for the workstation chassis is quite acceptable.

As it would combine well with other components, like a rack UPS, it suddenly starts to help save space rather than using more space.

Has anybody had experience with any server chassis between 4U - 6U that has large 140mm quiet fans and accepts regular fanless PSU?

Even if it is not so big, has anybody had any experience making a rack case operate quietly with water cooling?

Operating Systems and Porting / Re: any test servers for developer access?
« on: September 30, 2020, 05:32:14 pm »
Are any of those sites able to provide a graphical desktop (e.g. VNC) or they only provide shell access?

Operating Systems and Porting / any test servers for developer access?
« on: September 30, 2020, 02:27:56 pm »

I've been discussing a rendering bug with the Blender developers

I suspect the most efficient way for them to investigate would be having their own hardware but if that is not possible, remote access to a demo workstation at Raptor or any other user who has a spare Talos II or Blackbird right now.

Is there anybody who can help out in cases like this?

The vast majority of things I tried are working fine though.  This Blender bug is one of the few cases where something did not work.

Blackbird / Re: [amdgpu] [Fiji] Fedora 32 Linux kernel 5.7.x crashes
« on: September 27, 2020, 11:59:10 am »

Motorola?   Talos II + RTL-SDR is my radio

gqrx (and GNU Radio) just works installing the packages. Please remember not to plug in the RTL-SDR dongle until after you install the packages.

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