What Have You Done Today - (Computer Version)

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You did that in Python? That's really cool. When I was a student I messed around with a tool called "POV-ray" where you described the scene using a kind of mathematical markup and then rendered it. The scenes would take hours on an Atari ST.
 
Quick question. I have a 15 year old program (CorelDrawX3) that I'd really like to get working with Windows 10 Home... but it won't install (and not in compatibility mode). Any pointers? Changing software is undesirable since I believe I will loose some really specific functionality.
 
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GilesGuthrie
You did that in Python? That's really cool. When I was a student I messed around with a tool called "POV-ray" where you described the scene using a kind of mathematical markup and then rendered it. The scenes would take hours on an Atari ST.
Click to expand...
Yep, it was all in Python. We basically create a 3D coordinate system with triangles and spheres. Then produce rays coming from a "camera" and see if it intersects anything. Then calculate shading using Blinn-Phong shading, do recursive shading for reflections, etc. In the end, it was super easy.

box_final_4k.png


This 3840 by 2160 picture of the Cornell box obj file I found online took 205 minutes to render after some optimizations I added.
 
Today, and for the first time, I was able to use the Chromecast feature to stream material from one device to my TV monitor. I had the most success casting to my Roku Stick than I did using my Android TV box to do the same thing. I was not sure what all devices were hooked into my house from WiFi. So I looked up the main one I thought would connect to my TV. I bet if I bought a new TV that could easily be able to connect to a local WiFi network, I may be able to connect to it without needing to have a device like my Roku Stick.

I am fairly new to this, but I also tried casting to my Roku Stick using YouTube on my desktop. I did not know how to disconnect between desktop YouTube and the YouTube app on my Roku Stick. I then found a way to do so. And now I know how to utilize Chromecast. Since I have been considering getting the new Google Chromecast With Google TV, it is something I may want to look as I Feel like moving on from my Android TV box.


[UPDATE] I have recently gotten my Android TV box (Xiaomi Mi BOX S) to work with being able to Cast to TV. I just couldn't previously get the Android TV box to be recognized among the different devices in my house. So I don't have to rely on my Roku to be able to cast to TV. I also don't have to rely on my smartphone or my tablet PC to cast to my TV. I am rather tickled pink about using Cast to TV. I even have been looking to see what all I can actually use to cast on TV besides YouTube. I don't use Netflix, Hulu, or anything like that, so I can't say I can use those as well.
 
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I saw a video about an "impossible puzzle from Stanford competitive exam", by MindYourDecisions. The problem was this:

I paid $a679b for 72 identical items, where a and b are unknown digits (0 to 9). If the price was a whole number, how much did each item cost?"
Click to expand...

In the video, two solutions were suggested, one "brute force" and one using logic. The second solution was pretty smart, using the fact that 72 is divisible by 8 and 9 and some division laws that states that for a number to be divisible by 8, the last three digits must also be divisible by 8, and that for a number to be divisible by 9 then the sum of all the digits must also be divisible by 9.

The brute force approach was extremely lazy, is was just "set the price to 1, then check 72*price and see if the digits match. If not, add 1 to the price and try again."

In pseudocode it would look like this:

Code: 
BruteForce_1
We have the sum v = a679b and the number of items n = 72
run this loop for around 10,000 times:
      set x = 1
      set w = x*n
      compare w to the known digits in v
      if it's a match: break the loop. The sum is w and the price per item is x.
     else: add 1 to x and continue the loop.

So I figured that surely there must be a better brute force approach and opened up Python. What I came up with was this algorithm:

Code: 
BruteForce_2
We have the sum v = a679b and the number of items n = 72
set a = 0 and b = 0 (6790 is the smallest possible value of v)
run this loop 10 times:
      set x = v/72 and round it up to the nearest integer (because the price needs to be an integer and it can't be lower than v/72)
      set w = x*n
      compare w to the known digits in v
      if it's a match: break the loop. The sum is w and the price per item is x.
     else: add 1 to a and continue the loop.

BruteForce_1 needed to run the loop 511 times before finding a match.
BruteForce_2 needed to run the loop 4 times before finding a match.

I timed both algorithms in Python, running them 100,000 times each. BruteForce_1 took 1 minute and 3 seconds. BruteForce_2 took 1.5 seconds.
 
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Urgh... supply woes continue. I've missed the boat (probably literally) on the next batch of Corsair SF750 power supplies for the boy's build. Now Overclockers are suggesting May 2021 for the PSU. So I'm looking at a 650W Seasonic unit. I have a Seasonic in my ATX desktop, and it's been fine. Plus 650W should be enough, whether I go 3080 or 6800XT for the GPU.

So, the current spec is:
  • AMD Ryzen 5 3600XT 3.8 GHz 6-Core Processor (in the house)
  • CRYORIG H7 ULTRA 59 CFM CPU Cooler (in the house)
  • Gigabyte B550I AORUS PRO AX Mini ITX AM4 Motherboard (in the house)
  • Corsair Vengeance LPX 16 GB (2 x 8 GB) DDR4-3600 CL18 Memory (in the house)
  • Western Digital Blue SN550 1 TB M.2-2280 NVME Solid State Drive (in the house)
  • Gigabyte GeForce GTX 1650 D6 WINDFORCE OC 4GB Graphics Card (expected early-December)
  • Cooler Master MasterBox NR200P Mini ITX Desktop Case (expected mid-December)
  • Seasonic Focus SGX 650 80+ Gold Fully Modular SFX Power Supply (no delivery date yet, perhaps mid-Jan)
  • Corsair K70 RGB MK.2 Wired Standard Keyboard (in the house)
  • Glorious PC Gaming Race MODEL O Wired Optical Mouse (in the house)
Should be a nice rig for him. The 1650 is an interim card pending sorting out supply of the new-generation cards. I have an ATX PSU that he can use (hanging out of the back of the case, LOL) until the SFX unit arrives
 
GilesGuthrie
Plus 650W should be enough, whether I go 3080 or 6800XT for the GPU.
Click to expand...
The recommended PSU for a 3080 is 750 watts. I would at least go with the 750 watt as you want the headroom on the PSU to stay within the units best efficiency range.
Skimping on the PSU s the last place you want to cut corners on your build. A lot of expensive components life may well depend on the ample and clean power that is supplied by that PSU.

GilesGuthrie
I've missed the boat (probably literally) on the next batch of Corsair SF750 power supplies for the boy's build. Now Overclockers are suggesting May 2021 for the PSU. So I'm looking at a 650W Seasonic unit. I have a Seasonic in my ATX desktop, and it's been fine.
Click to expand...
Actually I would rate the Seasonic brand of PSU's above those made by Corsair and between the two brands would prefer Seasonic.
Seasonic has been considered a leading brand of top shelf producers of computer PSU's for decades and about the only negative you may hear about their products maybe a slight premium in the price you pay to get one of the best PSU's available.
 
VFOURMAX1
The recommended PSU for a 3080 is 750 watts. I would at least go with the 750 watt as you want the headroom on the PSU to stay within the units best efficiency range.
Skimping on the PSU s the last place you want to cut corners on your build. A lot of expensive components life may well depend on the ample and clean power that is supplied by that PSU.
Click to expand...

I agree about skimping on the PSU. Inputting the details, Seasonic's power calculator says this system needs 518W, PC Part Picker's says 479W, and Optimum Tech ran testing which showed 533W with an overclocked 10900K. So while the power draw of a 3080 is around 350W, there's not a whole lot else in the system drawing significant power. The 518W predicted by Seasonic is 79% of the PSU output, so I have some headroom for inrush etc, and a stable system should settle to around the 80% mark. It also gives me scope for him to swap out the 3600XT for a 5800X as & when he wants to get more cores.

And then there's...

VFOURMAX1
Actually I would rate the Seasonic brand of PSU's above those made by Corsair and between the two brands would prefer Seasonic.
Seasonic has been considered a leading brand of top shelf producers of computer PSU's for decades and about the only negative you may hear about their products maybe a slight premium in the price you pay to get one of the best PSU's available.
Click to expand...

I agree with this exactly. I chose a Seasonic for my own rig when it was Black-Friday-discounted to be price-comparable with the Corsair of the same wattage. I have personal experience with both brands being dependable. For my son's build, I was always going to be choosing between Seasonic and Corsair, even before discovering that finding SFX power supplies with more than 600W is tricky at the minute. If I were looking at a lower quality PSU I'd definitely want to increase the wattage to compensate.
 
GilesGuthrie
I agree about skimping on the PSU. Inputting the details, Seasonic's power calculator says this system needs 518W, PC Part Picker's says 479W, and Optimum Tech ran testing which showed 533W with an overclocked 10900K. So while the power draw of a 3080 is around 350W, there's not a whole lot else in the system drawing significant power. The 518W predicted by Seasonic is 79% of the PSU output, so I have some headroom for inrush etc, and a stable system should settle to around the 80% mark. It also gives me scope for him to swap out the 3600XT for a 5800X as & when he wants to get more cores.
Click to expand...

Have you read about the power spikes that 38080s can draw? Was almost 600W with early drivers (and still about 500W), causing PSUs to trip out because their protection circuitry acted too quickly.

Here's a user-maintained list of known compatible PSUs I found useful. Broadly speaking it seems that most recent Seasonic and Corsair are fine, but Seasonics prior to their current lineup were often not (various other threads on EVGA forum).
 
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Grayfox
It is the job of the PSUs protection circuitry to act quickly
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Its job is to act "quickly enough" to prevent damage. Which, if the PSU is decent, is not "as quickly as possible". Transient loads are specified for electronic components alongside continuous ratings, and it's up to the PSU manfacturer to ensure none of those are exceeded and use better ones where needed to meet their own design target for transient handling.

Of course I'd still prefer to trust e.g. Seasonic rather than a cheaper brand that just happens to work with a 3080, that goes without saying really.
 
Outspacer
Of course I'd still prefer to trust e.g. Seasonic rather than a cheaper brand that just happens to work with a 3080, that goes without saying really.
Click to expand...

Seasonic are some of the best, esp their Prime TX lineup

A fanless 700w Titanium PSU.
96% efficiency under 50% load.
Damn,
 
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Grayfox
Seasonic are some of the best, esp their Prime TX lineup

A fanless 700w Titanium PSU.
96% efficiency under 50% load.
Damn,
Click to expand...

You get what what you pay for, and that's a fantastic unit! There isn't much left of its case though with all the ventilation, maybe not ideal for a PC case which has a separated off PSU compartment like mine.

I got a lowly Focus GX 850W at less than half the price of that (£110) and even it doesn't turn its fan on much, although I haven't got a 3080 to stress it with yet. It had no problem pumping 280W into my 8700K though, I was just nervous about the chip!
 
Outspacer
You get what what you pay for, and that's a fantastic unit! There isn't much left of its case though with all the ventilation, maybe not ideal for a PC case which has a separated off PSU compartment like mine.

I got a lowly Focus GX 850W at less than half the price of that (£110) and even it doesn't turn its fan on much, although I haven't got a 3080 to stress it with yet. It had no problem pumping 280W into my 8700K though, I was just nervous about the chip!
Click to expand...

I use a HX750i and while the fan doesn't come on until you use more than 400w, i have set the fan to run at 40% all the time to keep it cooler so it lasts longer.
Runs at least 10°C cooler with the fan.
 
Grayfox
I use a HX750i and while the fan doesn't come on until you use more than 400w, i have set the fan to run at 40% all the time to keep it cooler so it lasts longer.
Runs at least 10°C cooler with the fan.
Click to expand...

Wise. I don't use the fanless mode either, just tried it out. I'm guessing I managed a total draw of about 500W in some tests - TBH with all the fans ramped up I couldn't pick out the PSU fan's noise, by feel it was certainly higher than idle.
 
I've managed to order an RTX 3080 GPU, scheduled for delivery this week. Avoided all the scalpers, managed to get it by being quick to a stock alertt. I think I've paid about £20 more than I could have paid if I kept waiting for a cheaper store but I'm not too bothered by that.

Just waiitng on finding the Ryzen 5900x in stock somewhere reasonablly priced and then I can get started on putting the new PC build together.
GilesGuthrie
Urgh... supply woes continue. I've missed the boat (probably literally) on the next batch of Corsair SF750 power supplies for the boy's build. Now Overclockers are suggesting May 2021 for the PSU. So I'm looking at a 650W Seasonic unit. I have a Seasonic in my ATX desktop, and it's been fine. Plus 650W should be enough, whether I go 3080 or 6800XT for the GPU.

So, the current spec is:
  • AMD Ryzen 5 3600XT 3.8 GHz 6-Core Processor (in the house)
  • CRYORIG H7 ULTRA 59 CFM CPU Cooler (in the house)
  • Gigabyte B550I AORUS PRO AX Mini ITX AM4 Motherboard (in the house)
  • Corsair Vengeance LPX 16 GB (2 x 8 GB) DDR4-3600 CL18 Memory (in the house)
  • Western Digital Blue SN550 1 TB M.2-2280 NVME Solid State Drive (in the house)
  • Gigabyte GeForce GTX 1650 D6 WINDFORCE OC 4GB Graphics Card (expected early-December)
  • Cooler Master MasterBox NR200P Mini ITX Desktop Case (expected mid-December)
  • Seasonic Focus SGX 650 80+ Gold Fully Modular SFX Power Supply (no delivery date yet, perhaps mid-Jan)
  • Corsair K70 RGB MK.2 Wired Standard Keyboard (in the house)
  • Glorious PC Gaming Race MODEL O Wired Optical Mouse (in the house)
Should be a nice rig for him. The 1650 is an interim card pending sorting out supply of the new-generation cards. I have an ATX PSU that he can use (hanging out of the back of the case, LOL) until the SFX unit arrives
Click to expand...
I managed to get a Corsair RMi PSU from https://www.cclonline.com/ after using the notify function that lets you know when stock is in. You might get lucky with the one you want on there.

I’m still waiting for a couple of parts to arrive for my build, the only part I’ve not ordered yet is the CPU. I’m waiting for stock on a 5900x. Only ones I can find available are heavily inflated prices.
 
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GilesGuthrie
A 3080 at £20 over list is a good buy Dave.
Click to expand...
Yeah I feel like I got lucky with that. Hopefully the stock situation will improve by the end of the year.

Finally got a Ryzen 5800X for £450 as well, the availability seems to be starting to increase for those. Some online retailers are reportedly receving quantities in the hundreds each week now. I was torn between the 5800X and 5900X but for what I will be doing, there wasn't much difference in performance between the two but there was over £100 difference (a lot more on some sites). Once I had the chance to get the 5800X it swung it for me.

I'm just waiting on the case and CPU cooler to be delivered (hopefully Friday) and then I can get the build done. I've held back on updating the motherboard BIOS, I didn't want to start doing anything until I had everything and was ready to start putting it all together and testing.

I plan to do an out of case test to make sure all the components work before I mount it all in though, I could have done all that while waiting for the case to be delviered if the CPU cooler wasn't part of the same delivery. Given the 5800X doesn't come with a cooler I don't have a spare to test with which is a shame. But it should all be worth it.
 
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Today I decided to take a punt on fixing a problem I've had for a while, which is that I've got an Asus PG279Q (27", 1440p, 144Hz monitor with G-Sync) going to waste because I can't keep it set up anywhere and my PC is too far from the only place I could use the monitor on a temporary basis. To resolve it I've decided to buy a DisplayPort repeater and two 28AWG cables to make the ~4 metre run from my PC, past the TV and up to the dining table as shown below. In case it's not clear, my PC is the black box to the right of the TV with the plant on top. And no, the plant isn't watered in situ!

20201209_175206.jpg


£50 all in, there are VESA certified cables that claim to be capable of 8K at 60Hz at up to 5 metres for less money but I couldn't find any evidence that that was without DP1.4's DSC feature so I decided to not bother trying. It might arrive on Friday but could be as late as next Wednesday, I'm quite keen to get it sorted because as it is I can only play on the TV and where the sofa usually is, it's too far back for me to be able to see anything - in the photo we've moved the sofa and the coffee table forward by about two metres to be able to watch some subtitled films! I usually have to sit on a chair (luckily not one of the folding ones you can see in the photo) in the middle of the room and can only really use a controller while sat in it, I do have a Sova lapboard but it's too wide to fit between the arms on the chair...

Thing is, if this does work I'll need to buy a keyboard to use on the table because right now I've got the Sova (which is huge, thick and has cushions on the bottom) and a Logitech k830.

Edit: just played 10 flicker-free minutes of Forza Horizon 4 at 1440p, 144Hz so I think the solution works! I'm quite impressed.
 
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Finally finished building the new PC yesterday, sadly I could'nt use it on the TV last night because of the HDMI on the RTX 3080 being 3.1 and the TV 3.0 which was causing heavy flickering or loss of dsplay altogether. But I've paired it with a 4k Display to HDMI adapter today and it's all working fine.

Not tried any overclocking yet, I'll start that either this evening or over the next few days, but I've spent a couple of hours on Cyberpunk 2077 last night and with the settings to Ray tracing Medium it worked flawlessly and the PC itself barely making a sound. That's with all the fan curves stock and no overclocking. So Once I start overclocking I may have to start messing with the fan curves a bit to keep it near silent.

For anyone interested in RTX 3080's and noise, the card Im using is an MSI Ventus 3X, some reviews have complained about the noise, mine was barely audiable. But I do have it in a mid-Tower with great vantilation (Lian Li Lancool II Mesh) so it's not choked for cood air at all. I also have 2 140mm Silnt Wings 3 fans at the front pulling air in, another 140mm fan in the roof pulling air out and a 120mm at the rear pulling air out.

I have another 2 120mm fans that I was going to mounth below the GPU on the PSU shroud but the mounts and screws for the fan aren't compatible (screws too thick) so I'll review that situation another time. I could just drill the holes out so the larger screws will fit but I'd rather not at the moment.

20201210_105138[13767].jpg 20201211_090851[13793].jpg 20201212_094940[13792].jpg

The full specs are:

Lian-Li Lancool II Mesh performance Midi-Tower Case - Black
Gigabyte X570 AORUS MASTER (AMD AM4) DDR4 X570 Chipset ATX Motherboard
Corsair RMi Series 1000W Fully Modular 80+ GOLD Power Supply
be quiet! Dark Rock Pro 4 CPU Cooler
be quiet! Silent Wings 3 120mm PWM Fan x 3
be quiet! Silent Wings 3 140mm PWM Fan x 2
Thermal Grizzly Kryonaut High Performance Thermal Paste - 5.5g / 1.5 ml
Corsair Vengeance LPX Black 32GB 3600MHz 2x16GB DDR4 Memory Kit
Seagate Firecuda 2TB M.2 SSD + Seagate 2TB Baracuda HDD
AMD Ryzen 7 5800X Eight-Core Processor/CPU, without Cooler
MSI GeForce RTX 3080 Ventus 3X 10GB OC GPU

Really pleased with it all so far.
 
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That's a really nice rig @Dave A. One suggestion though is to run a second power cable to your GPU, rather than using the daisy-chain connector. It gives the PSU an easier time of running all that power to the GPU.

My son's NR200p case showed up on Saturday. I haven't had a look at it yet, but the shipping container is smaller than my computer's case on the desk!
 
Thanks @GilesGuthrie, that's a decent suggestions. I'll be going back inside at some point this week to sort out the fans on the PSU shroud and try a bit of overclocking.
 
Yeah, just cable-tie the two wires together to avoid too much spaghetti.

I do quite covet getting a custom Cablemod cable set done, but I can't quite bring myself to spend the £££
 
Just bought a Rosewill Prism S and 750W Gold modular power supply deal I saw on Reddit. I was looking at rehoming my setup at some point anyway because I wanted to upgrade down the line and both the motherboard and PSU won't handle what I want in the future.
 
So since my last fiasco with this XMP issues on post #3580 I have updated bios like 3 times since.
2 of those 3 times I just changed the MHz to 3000, and then after yesterdays update I tried XMP.
No errors no issues.
It appears that the profile changed during one of those updates and now I can run XMP.
 
Had a go at doing an inlaid design on the 3d printer... some tweaking will be needed...

Img_2469.jpg


Basic idea works fine - print the inlay first, one layer thick, then print the rest of the model - which has the inlaid part subtracted from it - on top with the other colour, keeping the bed hot in between so the print doesn't come unstuck.

I should note this test was done with a 1mm nozzle :lol: which is hilarious at how fast it prints, but needs tweaking to get a full and even coverage. Also the design needs the second circle out thickening a little since that ended up too thin. I just used the colours I happened to be using for the test - final colours will be orange on black of course, and with the text* ;)

* the smaller text might not be legible though
 
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Added a Schiit Modi dac, Schiit Loki EQ and a Schiit Asgard3 headphone amp as my gaming computers headphone system.
So far been pairing this with a set of Drop 6xx cans. Very satisfied with this set up and how it sounds.
I added the passive EQ as I am not a big fan of digital EQ. Also my main use of the EQ is if I am trying to lift the level of say voices or a particular sound within a game and it is just easier to reach over and turn the knobs on the EQ to get the desired results rather than enter and fiddle with a program to digitally do it..
As you can probably tell I do like the Schiit brand of products as well.
 
Merry Christmas, GTPlaneteers!

I got myself a Google Chromecast With Google TV device. Just this day first using it, it turned out to be as enticing as I thought it would be when I first did my research on it. I felt it was time to move on from my Xiaomi Mi Box S. I felt this would be the perfect way to do so. However, I will need to find some sort of USB hub that has a USB Type-C connection so I could do a bit more with the Chromecast With Google TV. I was most sort of disappointed with the handling of some programs through WiFi on the Xiaomi Mi Box S. It also was rather poor at times maintaining a connection and sometimes crashing and restarting.

Then later today, I got the surprise of my life when I found out my brother got me a brand-new HDTV for Christmas! I got a 32' Roku TV. I set it up and everything. Looks and sounds great! What I ended up deciding to do is make my old TV (which also served as my extra PC monitor) to be my secondary PC monitor. The weirdest thing I could do is to have a triple monitor setup if I knew how to do so. For now, though, I'm happy with having my two monitors ready to go while also having my TV do some of its own work. As for connection to my HDMI switcher, the device works just fine with everything I set up into it.

Fabulous Friday of tech for me in this post! Mind blown.
 
beziers.png

In my efforts to develop a curve design mod for Cities Skylines I created a Python script for generating curves with approximated clothoid transitions, represented as quadratic Bézier curves. The script requires three inputs: start vector, curve angle and either minimum radius or vector length. The output is a complete curve. In the picture above I have collected a number of curves based on the following design parameter:
radius = 360 / curve angle [meters/degrees]. The curve angle here ranges from 10 degrees to 180 degrees. The rings represent the road width, which in cities skylines is 16 meters for a basic 2-lane highway. The inner rings are 8 meters wide, roughly the size of a highway ramp.

The S-curves are not from the script, they were made by copying a curve and rotating 180 degrees.
 

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