maxtch

It can be their ISP too. Also certain ISP pairs have exceptionally bad connections.

It can be their ISP too. Also certain ISP pairs have exceptionally bad connections.

Well, for Ethernet, if you have multiple wired devices with open PCIe slots (desktop PCs) you can upgrade the LAN connection to 10Gbps using some cheap used Mellanox 10Gbps Ethernet cards and a relatively cheap TP-Link 10Gbps Ethernet switch.

The first thing I see is your memory speed. You are leaving 50% of your memory interface performance on desk. Enable XMP first. Memory bandwidth is a critical point for overall system performance, as everything else usually has to transit through main memory when being moved from one device to another.

I encountered this thermal grease, AI Technology COOL-GREASE ZXM in SEMICON Shanghai 2020 and asked them for a sample to test with. It arrived a few days ago, and here is what I found out.
 
This thermal grease is rated for 20W/(K·m). And the manufacturer claims that this is a phase-change non-curing epoxy type thermal interface material.
 
The test system is my daily driver Hackintosh: i7-9700K on Gigabyte Z390 UD, under a Thermaltake 120mm AIO inside HuntKey S400 4U rack-mount case. The baseline was another free sample I got, with a nominal thermal conductivity of 4.5W/(K·m). That thermal grease gave my CPU a maximum turbo power of 125W. The ZXM, 190W. Correspondingly, under the same fresh-install open-rack condition, it gave me 3530 Cinebench R20 points over 3275. And it also maintains a much cooler idle temperature, even in a server rack with 14 spinning platters and a dual Xeon behemoth not far below.
 
I am benchmarking it again after a few weeks of continuous use.

I encountered this thermal grease, AI Technology COOL-GREASE ZXM in SEMICON Shanghai 2020 and asked them for a sample to test with. It arrived a few days ago, and here is what I found out.
 
This thermal grease is rated for 20W/(K·m). And the manufacturer claims that this is a phase-change non-curing epoxy type thermal interface material.
 
The test system is my daily driver Hackintosh: i7-9700K on Gigabyte Z390 UD, under a Thermaltake 120mm AIO inside HuntKey S400 4U rack-mount case. The baseline was another free sample I got, with a nominal thermal conductivity of 4.5W/(K·m). That thermal grease gave my CPU a maximum turbo power of 125W. The ZXM, 190W. Correspondingly, under the same fresh-install open-rack condition, it gave me 3530 Cinebench R20 points over 3275. And it also maintains a much cooler idle temperature, even in a server rack with 14 spinning platters and a dual Xeon behemoth not far below.
 
I am benchmarking it again after a few weeks of continuous use.

I encountered this thermal grease, AI Technology COOL-GREASE ZXM in SEMICON Shanghai 2020 and asked them for a sample to test with. It arrived a few days ago, and here is what I found out.
 
This thermal grease is rated for 20W/(K·m). And the manufacturer claims that this is a phase-change non-curing epoxy type thermal interface material.
 
The test system is my daily driver Hackintosh: i7-9700K on Gigabyte Z390 UD, under a Thermaltake 120mm AIO inside HuntKey S400 4U rack-mount case. The baseline was another free sample I got, with a nominal thermal conductivity of 4.5W/(K·m). That thermal grease gave my CPU a maximum turbo power of 125W. The ZXM, 190W. Correspondingly, under the same fresh-install open-rack condition, it gave me 3530 Cinebench R20 points over 3275. And it also maintains a much cooler idle temperature, even in a server rack with 14 spinning platters and a dual Xeon behemoth not far below.
 
I am benchmarking it again after a few weeks of continuous use.

This is gonna be one of the rarer beasts: dual Xeon E5-2696v2, what was an OEM CPU that rumored to have powered Amazon EC2 for quite a while. It have 100MHz higher all-core boost than the Linus-tested E5-2697v2 and the same single-core boost, but it have 200MHz lower base clock. Since I have ample cooling, it is actually a better chip than E5-2697v2 to me. And since the compatibility is a bit spotty (that is, only Asus server boards and a few select Supermicro boards are confirmed to work with this,) it is much cheaper. This run is taken with my Asus Z9PE-D16 motherboard with a modded BIOS with Spectre/Meltdown patches active.

The used Xeon allow you to keep everything you already have: motherboard, RAM, cooler, etc. You just need to swap in the overclockable Xeon, dial in an overclock, and you are ready to go. If you go AMD, you will have to get both new motherboard and new cooler, and those all should count as part of the cost. Haswell still have the IPC edge over Zen 2, so clock for clock, core for core, E5-1660v3 is faster than Ryzen. Notice the single core Cinebench when E5-v3 pulled a draw with Zen+ with a lower clock. Xeons more than often have some crazy overclock headrooms since they are binned for lower voltages and lower temperatures to begin with, something you want for a good overclocker. I can forsee your E5-1660v3 running at 4.5GHz, a 50% overclock from its 3GHz base. Quad-channel memory and double the PCIe lanes are always welcomed. Quad-channel memory means you can get a lot more memory bandwidth. PCIe lanes means more peripherals. So the idea here is buy just a used E5-1660v3, drop it into your existing X99 board, overclock it, and enjoy.

AliExpress should ship globally, and you may find some cheap gems there. (Or if you want to, I can help as I live in China and can speak Chinese, so I can help you with getting items on Taobao and ship it out to you.)

A family member of mine is asking me for a replacement PC, and she explicitly asked me for a hand-me-down, specifically my Xeon E3-1231v3 build. That was my main workstation, so in order to transfer that machine out, I have to build a replacement for myself.
 

Namesake of the machine: Hagoromo Lala from Star Twinkle Precure. The new cooler fan has a fixed color LED ring on it, making it look similar to this pastel-colored anime character. Credits: LaytonPuzzle27.
 
Requirements for the rebuild:
It is a Hackintosh and it have to inherit an existing install, so Intel CPU only. (Switching between Intel and AMD based Hackintoshes requires at least a partial reinstall.) The upgrade is limited to CPU, cooler, motherboard and RAM. Everything else is inherited from the existing machine. It must not have less resources than my original build (4 cores, 8 threads, 32GB RAM.)  
Here is my build, with the upgrades applied:
CPU: Intel Core i7-9700K (8C/8T, 3.6/4.9GHz, unlocked) Cooler: Chinese brand cooler, closest equivalent would be Cooler Master Hyper 212. Mobo: Gigabyte Z390 UD RAM: 2x Corsair Vengeance LPX DDR4-3000 16GB = 32GB total. (2 free slots) GPU: Sapphire PULSE RX 580 2304SP 8GB (inherited) SSD: Samsung 960 Pro NVMe 512GB (inherited) SSD: Hyperdisk SDOM 8GB (inherited) HDD: WD Black 2TB (inherited) PSU: Antec 620W continuous (inherited) Display: Dell P2415Q 24-inch 4K over DisplayPort (inherited) Case: Rackmount My original plan was either buy an i7-4790K (I have a spare Z97 motherboard I can give to that family member) or a used i7-6700K + Z170 platform. However due to the coronavirus outbreak it is very difficult to buy used in China now. This means I have to bite the Intel tax (thanks to Apple) and buy brand new.
 
Here is a photo of the upgrade components (and the NVMe SSD) before it is put in the case:

 
FAQ
Q: What's up with that 8GB SDOM?
A: That is where Clover bootloader for macOS goes. By having Clover, its configuration files and Hackintosh-specific kexts away from actual drives that holds macOS, it allows me much more peace of heart when coming to system upgrades, knowing that macOS installer will not touch the Clover partition at all. Q: Why i7-9700K and Z390?
A: It is based on 2019 27-inch iMac. The actual iMac used either i5-9600K or i9-9900K, so i7-9700K is a half-way option. (It is a better match than you think, as 2019 iMac 27-inch came with Radeon Pro 580, an exact match for my RX 580 8GB.) Q: How is the storage arranged?
A: APFS Fusion Drive, with 2.5TB effective storage space. Q: Have you tried overclocking?
A: My cooling situation in the rack is bad, so even with just +0.25V voltage delta the cores are hitting 100 degrees Celsius. Memory works correctly though at DDR4-3000 through a XMP profile, and macOS correctly identified it.
 

A family member of mine is asking me for a replacement PC, and she explicitly asked me for a hand-me-down, specifically my Xeon E3-1231v3 build. That was my main workstation, so in order to transfer that machine out, I have to build a replacement for myself.
 

Namesake of the machine: Hagoromo Lala from Star Twinkle Precure. The new cooler fan has a fixed color LED ring on it, making it look similar to this pastel-colored anime character. Credits: LaytonPuzzle27.
 
Requirements for the rebuild:
It is a Hackintosh and it have to inherit an existing install, so Intel CPU only. (Switching between Intel and AMD based Hackintoshes requires at least a partial reinstall.) The upgrade is limited to CPU, cooler, motherboard and RAM. Everything else is inherited from the existing machine. It must not have less resources than my original build (4 cores, 8 threads, 32GB RAM.)  
Here is my build, with the upgrades applied:
CPU: Intel Core i7-9700K (8C/8T, 3.6/4.9GHz, unlocked) Cooler: Chinese brand cooler, closest equivalent would be Cooler Master Hyper 212. Mobo: Gigabyte Z390 UD RAM: 2x Corsair Vengeance LPX DDR4-3000 16GB = 32GB total. (2 free slots) GPU: Sapphire PULSE RX 580 2304SP 8GB (inherited) SSD: Samsung 960 Pro NVMe 512GB (inherited) SSD: Hyperdisk SDOM 8GB (inherited) HDD: WD Black 2TB (inherited) PSU: Antec 620W continuous (inherited) Display: Dell P2415Q 24-inch 4K over DisplayPort (inherited) Case: Rackmount My original plan was either buy an i7-4790K (I have a spare Z97 motherboard I can give to that family member) or a used i7-6700K + Z170 platform. However due to the coronavirus outbreak it is very difficult to buy used in China now. This means I have to bite the Intel tax (thanks to Apple) and buy brand new.
 
Here is a photo of the upgrade components (and the NVMe SSD) before it is put in the case:

 
FAQ
Q: What's up with that 8GB SDOM?
A: That is where Clover bootloader for macOS goes. By having Clover, its configuration files and Hackintosh-specific kexts away from actual drives that holds macOS, it allows me much more peace of heart when coming to system upgrades, knowing that macOS installer will not touch the Clover partition at all. Q: Why i7-9700K and Z390?
A: It is based on 2019 27-inch iMac. The actual iMac used either i5-9600K or i9-9900K, so i7-9700K is a half-way option. (It is a better match than you think, as 2019 iMac 27-inch came with Radeon Pro 580, an exact match for my RX 580 8GB.) Q: How is the storage arranged?
A: APFS Fusion Drive, with 2.5TB effective storage space. Q: Have you tried overclocking?
A: My cooling situation in the rack is bad, so even with just +0.25V voltage delta the cores are hitting 100 degrees Celsius. Memory works correctly though at DDR4-3000 through a XMP profile, and macOS correctly identified it.
 

Miners' RX 470 are likely better deals if you are just SR-IOV'ing.

If you want to put nVidia GPU in VM's I think the only cheap solution is hacking those Teslas into GRID's and pass them through using vGPU. As of passing AMD GPU, those mining RX 470's flashed with gaming VBIOS passed over SR-IOV are good options since those cards are cheap and lacked video output.
 
Anyway, after it is done you can just put the server somewhere out of earshot, and use a bunch of Pi's in the rooms as thin clients.

If you want to put nVidia GPU in VM's I think the only cheap solution is hacking those Teslas into GRID's and pass them through using vGPU. As of passing AMD GPU, those mining RX 470's flashed with gaming VBIOS passed over SR-IOV are good options since those cards are cheap and lacked video output.
 
Anyway, after it is done you can just put the server somewhere out of earshot, and use a bunch of Pi's in the rooms as thin clients.

Since you have that much compute power, you can replace other PC's in the room with Raspberry Pi's acting as thin clients.
 
Meanwhile if you have the funds, you may want to scoop up some of those 4TB Intel DC P4000 NVMe SSD's Facebook was dumping, and a maybe one of those nVidia Tesla cards that can be modded into a GRID. The former are just some cheap and fast SSD, and the latter will allow you assign virtual GPU to the VM's. 

If it is a kids computer, given the current market, either going used or going Ryzen 3000G would be the smart move. E3-1270v6 is an awkward chip to use as Intel blocked its use on desktop boards (expensive boards) and it requires discrete GPU. (I am also using an E3, but E3-1231v3, which works on regular desktop Haswell boards and had an interesting pricing, so there is some value prospect in it.)
 
I would suggest a machine with a Ryzen 3000G APU, leave space open for a future GPU, 16GB dual channel RAM, and a 480GB NVMe SSD. That would be a good mid-range with future upgrade path.

Nitpick: you will lose memory performance if you are using just one stick of RAM per processor. Those Xeons uses quad-channel RAM, so with two of them you need 8 matching sticks of memory for best performance.

I wish I had that kind of transfer speeds when I am restoring my backups.
TL;DR, sorry. Just keep in mind that some workloads you might throw at that processor can be demanding on memory bandwidth, for example DBMS, for example code compile with aggressive optimization and parallelized to the thread.

If, for example, you implement on-the-fly full-disk encryption, you need strong compute. Although for a storage server it is better to implement that on the client side so the server never sees the cryptographic keys. Or if your server also hosts a DBMS compute is needed to deal with the requests.

Depending on what you do. If it is a pure storage server the memory bandwidth won’t matter much. But if you compute on it, it becomes very taxing on the memory bandwidth.
 
I have an ex-server workstation I compile code on. Compiling code with aggressive optimizations on is a strictly CPU-only, integer-only, high throughput, high IOPS compute task if parallelized. Not only do I need octa-channel memory, but also NVMe SSD, to keep my dual Xeon E5-2680 fed.

Nitpick: you will lose memory performance if you are using just one stick of RAM per processor. Those Xeons uses quad-channel RAM, so with two of them you need 8 matching sticks of memory for best performance.

Nitpick: you will lose memory performance if you are using just one stick of RAM per processor. Those Xeons uses quad-channel RAM, so with two of them you need 8 matching sticks of memory for best performance.

For a server it might be cheaper to just use the integrated GPU. Then you can use your PCIe slots for other things.

If you have spare PCIe lanes you can try add an used IBM M1015 and force flash it into LSI 9211-8i IT-mode SAS HBA card. That gives you 8 additional SAS lanes which can be used as 8 SATA ports. Those are ex-server hardware, often cheap and lasts a long time.