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WHAT'S UP
A modest cryptocoin miner.
| CPU temperature monitor | coretemp, ISA bus | lm_sensors |
| CPU frequency scaling | p4_clockmod | powernowd or similar |
| Ethernet | r8169 | |
| Integrated graphics | i915 | |
| SATA | AHCI | See below |
| Sound | Intel HDA, Realtek implementation | model=3stack-dig |
| Graphics | fglrx / Radeon SI | See below for opensource drivers |
| WLAN | ath9k |
Apparently, many Atom processors have Enhanced SpeedStep for proper frequency and voltage control, similar to Pentium M and the various Core series. However, this one does not. I guess it is OK to waste power and generate heat just because it is a 'desktop' model :-/
However, there is still the old P4 clock modulation. It is not really a frequency scaler, more like throttling by skipping clocks. (There is also a separate sysfs interface for throttling, which achieves the same goal.) Due to the high switching latency, dynamic conservative/ondemand governors do not work, and a userspace daemon like Powernowd is required.
I don't use any of this though, since the CPU is cool and low-power even at full load. No fans are needed if you have any kind of airflow around, from GPU fans etc. or a sufficiently open case. I have used a number of low-power mini motherboards that don't quite survive full loads sans fans, despite the appearance. In contrast this Atom is rock solid, though admittedly slower too.
This motherboard only has 2 internal SATA ports that really work, and they are easily covered by a GPU cooler. That way only one can be used, with an angled connector. The eSATA port works fine though.
See the old hoo's note for further details.
See the old hoo's note. This is actually usable, and worth running 4 threads in most cases.
The integrated HDMI is limited to a maximum resolution of 1366x768. Moreover, this must be chosen from BIOS, as it appears as a fixed-resolution LVDS panel. The integrated VGA also has a weird resolution limit, though higher than the HDMI. These seem like marketing choices rather than technical limitations; an older Intel GPU in my other machine handles higher resolutions just fine, though it has similar LVDS quirks.
Using the Intel graphics simultaneously with fglrx is impossible, because Intel requires KMS, but fglrx does not allow it. At the moment, it would be possible with the opensource Radeon drivers, but OpenCL is still not very practical.
Furthermore, the integrated graphics should be disabled in BIOS to get the fglrx setup working.
See Hoo for the old notes.
[2018-04-15] Over the past year or so, I have been testing the opensource Radeon/AMDGPU drivers. The primary reason is that the fglrx drivers are getting old and unsupported, so I need to use an older kernel Xorg components. As I have moved mostly to Nvidia, this remains my only machine with a discrete AMD GPU, so I have little reason to patch the driver as I used to do. The open driver framework has also seen steady development, and it looks like it's finally paying off: the open Radeon driver vastly outperforms fglrx in Boolberry mining.
Kernel graphics config:
<*> /dev/agpgart (AGP Support) ---> -*- VGA Arbitration (16) Maximum number of GPUs [ ] Laptop Hybrid Graphics - GPU switching support <*> Direct Rendering Manager (XFree86 4.1.0 and higher DRI <*> ATI RadeonNote in particular, Southern Islands (here Tahiti, HD 7970) still uses the older Radeon driver. The newer AMDGPU driver has experimental support for SI, but it hasn't worked for me. The real action is with the Mesa OpenCL/GL libraries powered by LLVM, which is where the recent boost came up; BBR miner speed more than doubled upon Mesa and LLVM upgrades. For Gentoo, I use
VIDEO_CARDS="amdgpu radeon radeonsi"just to be sure, as I keep testing the AMDGPU framework occasionally.
With opensource drivers, the Intel and AMD GPUs can be used simultaneously with a suitable xorg.conf. As noted above, this Intel isn't particularly useful in comparison, but it might come in handy.
[2018-08-30] Mesa on Radeon provides both VDPAU and VAAPI to access the GPU video decoder, most importantly for H.264. VDPAU is more widely supported by software, and seems technically better too.
As seen before, the WD hard drive has the idiotic 8-sec spindown by default. See old nanite page for more; I used idle3-tools to disable it, as regular spindown timer is enough.
Yet another fantasy character with a name suited for mining.