Two very large servers are needed for VLSI layout: * fastest single-core performance (multi-core is not useable) * NVMe SSDs (not large ones, 256 or 512 GB is fine) * 128 GB or 256 GB of fastest RAM
Staf the size of the VLSI layout is so large that some monster machines are needed. we assumed you would need one. RED will get two, keep one as an asset "on loan" to LIP6. the Dell 3660 Tower looks extremely powerful: 12 gen i9, 30 MB L3 Cache, 128 GB RAM and liquid cooling.
(In reply to Luke Kenneth Casson Leighton from comment #1) > Staf the size of the VLSI layout is so large that some monster machines > are needed. we assumed you would need one. RED will get two, keep one > as an asset "on loan" to LIP6. > > the Dell 3660 Tower looks extremely powerful: 12 gen i9, 30 MB L3 > Cache, 128 GB RAM and liquid cooling. dell has a poor reputation when it comes to cooling and performance and reusability for desktops: https://youtu.be/UnvxSkqJ8ic in my opinion we should instead get the parts needed to build our own computers, because we can get what we need rather than pay a bunch extra to get something with worse performance and poor reusability later. I recommend air cooling because if you get the right cooler it has similar performance to liquid cooling but without the maintenance hassle. gamersnexus thinks the best cooler is the Scythe FUMA 2, which is an air cooler. https://youtu.be/Vex9_84VpYs the ryzen 5800x3d (not 5800x) has the best single-threaded performance for things that need lots of cache -- it is faster than the core i9 12900k in that regard. currently most ddr5 ram is slower than the best ddr4 ram because ddr5 is still very new. assuming we're getting an amd cpu, we'd want 4x 32gb sticks of ddr4 3600mhz c16 ram (c16 is the fastest I can find unless you're ok with 16gb sticks). don't get higher frequency ram because amd cpus have to switch their fclk to be 2:1 rather than 1:1 which causes higher latency and lower performance. make sure to enable XMP/DOCP/etc. in the bios otherwise the memory will run at a much lower than advertised speed. for a motherboard, more or less any decent am4 motherboard should work, which one you want will depend on local availability. see https://www.anandtech.com/show/12072/best-motherboards for a few good ones. the 5800x3d doesn't have a built-in gpu, so you'll need a separate gpu for initial setup at least. just in case you don't know: make sure to plug video cables into the gpu and not the motherboard's video output...the motherboard's video outputs only work when your cpu has a built-in gpu. the computer case will need to support the motherboard and cooler you pick, and will need good cooling. gamersnexus best case for 2021 is the fractal torrent, which is compatible with nearly everything: https://youtu.be/YtyWUAjmmZA imho pick the steel side panels variant rather than glass since it's waay more durable (i could care less about rgb lighting). you will want storage, i'd pick a >=1tb m.2 ssd, make sure to get one that has a dram cache otherwise it'll have terrible performance.
LIP6 needs the reliability of a warranty that comes with engineers who will simply replace the machine if necessary. unfortunately they don't need the hassle or have the luxury of time to assemble, disassemble, troubleshoot or deal with out of warranty parts in just over one years' time. the ability to "make it someone else's problem" is a good enough reason to not have to chase the last few percentage points of performance. liquid cooling is quieter and Jean-Paul's office often exceeds 32C.
(In reply to Luke Kenneth Casson Leighton from comment #3) > LIP6 needs the reliability of a warranty that comes with engineers > who will simply replace the machine if necessary. unfortunately > they don't need the hassle or have the luxury of time to assemble, > disassemble, troubleshoot or deal with out of warranty parts in > just over one years' time. the ability to "make it someone else's problem" > is a good enough reason to not have to chase the last few percentage > points of performance. well, at least get it from someone other than dell...there are reputable companies that will build a pc to your spec and offer a warranty on it. gamersnexus liked maingear's build quality: https://youtu.be/-VVC1NOgqeg 128gb ram and 5800x3d and amd rx 6600xt gpu (because it works without proprietary drivers on linux and is the cheapest amd gpu they offered) and 1tb m.2 ssd and closed-loop liquid cooler: https://maingear.com/cart-share/nmgdB you can select a longer warranty (2 or 3 years) if you want to pay for it. > > liquid cooling is quieter and Jean-Paul's office often exceeds 32C. there are very quiet air coolers...
(In reply to Luke Kenneth Casson Leighton from comment #1) > Staf the size of the VLSI layout is so large that some monster machines > are needed. we assumed you would need one. RED will get two, keep one > as an asset "on loan" to LIP6. The first need is for you, e.g. red and LIP6; during development there the runs will be done. I also have access to LIP6 at the moment so I can decide what to do when closer to the deadline and based on your experiences. For my final (few) runs I could even go cloud or so. I do think the main question is if 128GB of memory will be enough; if not we may need to go for HEDT (threadripper, core-i ... X) or even server (EPYC/XEON). From the other side Gabrial Govine is working on improving the speed of the placer which I hope will help us a lot
FYI, I have also been looking at refurbished equipment; like Maas Computers(https://www.maascomputers.nl/) for workstations or Tonitrus(https://www.tonitrus.com/) for servers. Of course for best single core performance it's best to go for most recent CPUs.