eBay - Intel Xeon E5-2680V4 - $168

RobstarUSA

Active Member
Sep 15, 2016
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I virtualized my FreeNAS instance running on Xeon x56**, and the latencies for my Optane-drive went from 15μs to 240μs. I started seeing if i could bring this down again and after getting it to 190μs I hit a brick wall and ended up in contact with the VFIO kernel-maintainer and was told that the hardware just is that slow to do the vmentry/vmexits. There was generational improvements, but the big one apparently is Posted Interrupts, that appears with the Xeon v4's.
Did you pass the optane drive directly through to the VM?
 

josh

Active Member
Oct 21, 2013
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Dipping my toe into V3/V4, is this worth being double the cost of E5-2678V3?
 

JoshDi

Active Member
Jun 13, 2019
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Dipping my toe into V3/V4, is this worth being double the cost of E5-2678V3?
Depends on your use case. V4s have higher memory throughput and better performance if you are using the machine for VMs.

V3s do have the ability to have all cores run at turbo (via the known bug/feature), which does not work on V4s.
 

josh

Active Member
Oct 21, 2013
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Depends on your use case. V4s have higher memory throughput and better performance if you are using the machine for VMs.

V3s do have the ability to have all cores run at turbo (via the known bug/feature), which does not work on V4s.
So if you turn on turbo on V3 it's a 12C 3.3GHz vs 14C 2.4GHz for half the cost?
I've never tried either chip so I'm not sure if I should start with V3 or jump straight to V4.
They will be used for VMs.
 

itronin

Well-Known Member
Nov 24, 2018
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Denver, Colorado
So if you turn on turbo on V3 it's a 12C 3.3GHz vs 14C 2.4GHz for half the cost?
much higher cooling requirements both for the CPU and VRM with ACT. if this is going into a custom built chassis where you have vertical space and/or chassis real-estate very-doable and could be very cost-effective. If going into say a 2U chassis (like a quanta for instance ;)) you will experience increased fan load (noise) due to increased temps and its possible the stock cooling may not be able to keep the CPU and VRM cool engouh - I don't know - just raising the possibility. I'd be very leery about trying to run dual CPU's with ACT - definitely research that.

I'm only using ACT and single 2678v3's with cheap chinese motherboards in gaming/home chassis with lots of cooling options.

You'll also have to mod the BIOS for the target systems to run ACT. What kind of systems are you looking to deploy this into?
 

josh

Active Member
Oct 21, 2013
530
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much higher cooling requirements both for the CPU and VRM with ACT. if this is going into a custom built chassis where you have vertical space and/or chassis real-estate very-doable and could be very cost-effective. If going into say a 2U chassis (like a quanta for instance ;)) you will experience increased fan load (noise) due to increased temps and its possible the stock cooling may not be able to keep the CPU and VRM cool engouh - I don't know - just raising the possibility. I'd be very leery about trying to run dual CPU's with ACT - definitely research that.

I'm only using ACT and single 2678v3's with cheap chinese motherboards in gaming/home chassis with lots of cooling options.

You'll also have to mod the BIOS for the target systems to run ACT. What kind of systems are you looking to deploy this into?
The 2U quanta in the thread below lol. I was going to migrate a V2 C6220 proxmox cluster. Currently using E5-2650V2s. Might migrate the desktop as well. That's running a E5-2697V2 right now.
I guess I didn't really think about the cooling issue.
 

JoshDi

Active Member
Jun 13, 2019
178
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So if you turn on turbo on V3 it's a 12C 3.3GHz vs 14C 2.4GHz for half the cost?
I've never tried either chip so I'm not sure if I should start with V3 or jump straight to V4.
They will be used for VMs.
For VMs Id go to the v4 because it handles interrupts with VMs way better. There is an issue with v3s that can cause latency when used with VMs.

There is no E5-2678 v4 but I run a E5-2680 v4 with turbo enabled. It runs at 2.9ghz for all cores, or higher ghz if cores are parked.

For information about the v3 turbo unlock "bug" ,read this: freecableguy/v3x4
 

josh

Active Member
Oct 21, 2013
530
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For VMs Id go to the v4 because it handles interrupts with VMs way better. There is an issue with v3s that can cause latency when used with VMs.

There is no E5-2678 v4 but I run a E5-2680 v4 with turbo enabled. It runs at 2.9ghz for all cores, or higher ghz if cores are parked.

For information about the v3 turbo unlock "bug" ,read this: freecableguy/v3x4
Don't think I'll be doing turbo after remembering stressing the CPU = unbearable fans.
Do you have a link about the latency issue? Is the difference between V3 and V4 noticeable between processors with same clock/core count?
 

JoshDi

Active Member
Jun 13, 2019
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koifish59

Member
Sep 30, 2020
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So if you turn on turbo on V3 it's a 12C 3.3GHz vs 14C 2.4GHz for half the cost?
You should also take IPC into account. Even at base clocks, a 2.4ghz v4 (14nm) should still be slightly faster than a 2.5ghz v3 (22nm).
 

cooldude919

New Member
Sep 8, 2016
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page doesnt exist on ebay
I found it

They also have a listing on alibaba. I cant find anything else with a quick google search, and the ink/labels on the top look a little beat up when you compare it to the esiso v4 listing.

It could have been a ES type rebaged, or a one off small build for a hyperscaler or something, but id certainly not jump on it myself, given with shipping the cost is a good chunk more than the regular v4 listing, why take the risk?
 

JoshDi

Active Member
Jun 13, 2019
178
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I found it

They also have a listing on alibaba. I cant find anything else with a quick google search, and the ink/labels on the top look a little beat up when you compare it to the esiso v4 listing.

It could have been a ES type rebaged, or a one off small build for a hyperscaler or something, but id certainly not jump on it myself, given with shipping the cost is a good chunk more than the regular v4 listing, why take the risk?
I cant find any information about this "upgraded" 2680v4 processor anywhere.
 

josh

Active Member
Oct 21, 2013
530
137
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page doesnt exist on ebay
My bad, bad url copy

I cant find any information about this "upgraded" 2680v4 processor anywhere.
I found it

They also have a listing on alibaba. I cant find anything else with a quick google search, and the ink/labels on the top look a little beat up when you compare it to the esiso v4 listing.

It could have been a ES type rebaged, or a one off small build for a hyperscaler or something, but id certainly not jump on it myself, given with shipping the cost is a good chunk more than the regular v4 listing, why take the risk?
It certainly looks fishy. Which is why I was checking if anyone had more information on it. Could have been another E5-2678V3 situation.

Regarding shipping, I'm not located in the US so I need to pay a forwarder for shipping anyway.