Some may recall I decided to try some Linux on crunchers, with one install done so far. My other box has a non-activated copy of Windows that will need replacing shortly so I need to get on top of Linux.

Tonight's job was to install VNC. I use tightvnc on all my Windows systems, not in any secure way. I like to take control of a PC as if I were sitting there. I specifically don't want a virtual desktop or login. Just let me control the box as if I were sitting in front of it.

So, in Linux mint (cinnamon desktop) I went to find one, and saw tightvnc server offered, and installed it. TightVNC is the package (server and viewer) I already use in Windows. Erm... now what? I saw nothing happen. A quick trip to google later, I had ran some commands that (apparently) set a password and started the server. Great.

Back to my main desktop, I tried to connect. Nope. I got an error saying the connection was refused. After a bit more poking around, I inadvertently started a 2nd server so I thought I'd connect to that by entering the alternate port in viewer, and it worked! Kinda... it gave me a tiny virtual desktop, with an error message saying cinnamon had crashed. So, not what I wanted anyway.

Back to google, and it now looks like vnc is built into cinnamon already, but not in any easy to enable way. Thanks.
http://ask.xmodulo.com/enable-configure-desktop-sharing-linux-mint-cinnamon-desktop.html

After following the above instructions, it almost worked. I create a custom password which didn't work. Used the one given there as example, it did work. I've always like to live dangerously, and decided to turn off passwords totally. If someone gets in my home network, I have more things to worry about than if they stop my BOINC client!

Now, I probably need to do some cleaning. Chances are tightvnc is still there serving up those extra bits I don't want, and I saw it add entries to startup and have no idea how to remove them...

XP is not an option really since I need 64-bit. Well, I guess there is XP64 but did anything ever really support that?

As mentioned in another thread, I am an eternal veteran noob when it comes to Linux. I know what can be done, just not how to do it.

XP is not an option really since I need 64-bit. Well, I guess there is XP64 but did anything ever really support that?

Yes everything that the 32bit version did, most people just didn't use it because they only had 32bit machines.

Ok, out goes the test Win7 install, and I have another Linux Mint install and boinc running, with VNC configured. Getting much faster at this. I'd like a SSD but don't have any free at the moment so just used an ancient 320GB hard disk. It was high end in its day, about a decade ago! If I'm reading the "top" output correctly ram usage of the operating system is practically nothing compared to Windows, at about 1.5GB including BOINC.

I took the chance to move some bits around. I'm debating retiring the R9 280X. I bought it for its DP performance but it is so power hungry when running, and for GFN OCL3 it is comparable to a GTX 960 at half the power consumption. It is still fast for OCL I believe, but don't currently have any intent to run the higher GFN projects, assuming they still use OCL.

On that note, I moved both my GTX 960s into my Sandy Bridge box. As that is my oldest active CPU, I'm losing less when the cores are left free to drive the GPU later. By coincidence, the motherboard doesn't have both GPUs right next to each other so I should have less heat problems on the upper GPU compared to when I tried this previously in my Skylake box.

Also, I'm wondering do I even need add in GPUs? My thinking is as follows: I've typically used GPUs in all machines so that integrated graphics wont steal memory bandwidth. But the GPU is rarely used anyway, and even idle it is consuming some power. So I did a quick test and saw no difference on a i3-4150T system running GPU or Intel integrated graphics for CPU GFN n=17 tasks, which themselves don't need ram bandwidth either.

As a final adjustment to power optimisation, I've disconnected the DVD drives. Apart from OS install, I don't think I need them any more. Even then I could move the media to USB drives.

Anyone have any thoughts/advice on linux (amd/ati) gpu tweaking? I have amdoverdrivecntrl installed on xubuntu 15.05, and on another (identical hardware) windows7 box, msi ab. GPUs are 7990s.

On the windows box, I can adjust voltage. Specifically, I can undervolt the card down to 1.1v. On the windows box, I cannot adust gpu or memory frequency. Any settings changes result in no actual change on the card.

On the linux box, I can adjust gpu and memory frequency, but not voltage, which means I run a bit hotter than I really want to.

Ok, just had my first security scare.

I VNC'd into one of the linux boxes and saw what appeared to be the confirmation screen of a purchase. I didn't make it, no one else physically had access. It looked real, and the browser history looked real. At first I assumed it was some weird pop-up advert from a forgotten browsing session, but according to the history nothing else happened recently. This happened around midday yesterday when I would have been at work.

On the assumption this was an intrusion, how could they have got in? I checked the DHCP clients, nothing unusual in there. I also have powerline networking at home, that is supposed to be limited internally right?

While randomly poking around the router settings, I saw the smoking gun. Under UPnP, I saw the IP address of that machine and port 5900 - VNC. Unknown to me, a VNC server decided to expose itself to the outside world. Under the mistaken belief VNC would only be accessible from my internal network, I didn't set a password on that connection... great. The whole internet could have used that machine. If that browser window hadn't been left open, I would be none the wiser that anything was going on at all.

The odd thing is, my other linux box, with near enough identical configuration, doesn't expose that port through the router. I'm wondering if the 1st box was exposed since I was messing around with different VNC servers trying to find a combo that worked.

So now there has been a high probability someone made a fraudulent purchase, presumably with stolen details, appearing to come from my network. Great.

As I said, unknown to me VNC on that machine opened up a port on my router through UPnP mechanism, exposing itself to the internet. Obviously that was never intended. I have disabled UPnP on the router now and will see if that breaks anything. I've also taken that machine offline and putting Win7 back on temporarily while I decide what to do long term.

Tonight, I have mostly been playing with Ubuntu. Since the earlier security scare, I thought it safest to nuke and reinstall on the two linux boxes. I don't want to perpetually mess around with un-activated Windows installs, nor pay again for Windows, so thought I'd give Ubuntu another try. Downloaded 15.10 and installed it easily enough. It feels more polished than Mint 17.2, but I'm not sure about the interface. In particular, they've hidden mouse acceleration which would be a deal breaker for this to be used as a desktop. But I got VNC going, this time with password turned on, so I can use it with the mouse response of the host. Have also put BOINC on and that's crunching away.

If I understand correctly, Mint 17.2 is based on Ubuntu 15.4, so one version back from current Ubuntu. Installed through their respective installers, I note Mint has an older version kernel and boinc. I'm sure the more adept than me can get newer boinc running easily, but at least Ubuntu 15.10 is on 7.6.x so no silly time estimates like on 7.2.x from Mint.

I think I'll take a break there.