Go Back   OC3D Forums > [OC3D] General Forums > OC3D News
Reply
 
Thread Tools Display Modes
 
  #1  
Old 06-11-18, 07:19 PM
WYP's Avatar
WYP WYP is offline
News Guru
 
Join Date: Dec 2010
Location: Northern Ireland
Posts: 13,534
AMD's Zen 2 EPYC Processors will offer up to 64 Physical Cores

A 2x increase over 1st Generation EPYC.



Read more about AMD's 64-core Zen 2 EPYC processors.

__________________
One of these days I'll change my name to Mark Bench
Reply With Quote
  #2  
Old 06-11-18, 07:22 PM
NeverBackDown NeverBackDown is offline
AMD Enthusiast
 
Join Date: Dec 2012
Location: Middle-Earth
Posts: 15,051
Only a 2x increase in performance? I'd say that's actually worse than expected considering they double core/thread counts.
__________________
The Cost of Freedom -
"A price payed gladly, in the hopes that the free, live better."
Reply With Quote
  #3  
Old 06-11-18, 07:34 PM
AlienALX's Avatar
AlienALX AlienALX is offline
OC3D Elite
 
Join Date: Mar 2015
Location: West Sussex
Posts: 11,277
I would guess they mean IPC. However, it all depends on how Zen 2 clocks. If it clocks higher (and it should, really) then the difference will be more pronounced.

Now I can see why Intel are bricking it and making 48 core CPUs though. It makes sense now.
__________________
He used to do surgery
For girls in the eighties
But gravity always wins



Reply With Quote
  #4  
Old 06-11-18, 07:37 PM
WYP's Avatar
WYP WYP is offline
News Guru
 
Join Date: Dec 2010
Location: Northern Ireland
Posts: 13,534
Quote:
Originally Posted by NeverBackDown View Post
Only a 2x increase in performance? I'd say that's actually worse than expected considering they double core/thread counts.
Remember that this is a server part and that power and thermals are a major factor. It's impressive that they got a 2x increase from 2x the cores, never mind the 4x increase in floating point.
__________________
One of these days I'll change my name to Mark Bench
Reply With Quote
  #5  
Old 06-11-18, 07:38 PM
tgrech tgrech is offline
Member
 
Join Date: Jun 2013
Posts: 133
You can't get a 1:1 2x in performance just be doubling core counts (See Amdahls law). Combined with the fact that the number of memory channels has to remain at 8 so bandwidth/core will likely be little more than half, and the fact that you've now got the thermal output of twice the number of cores in the same size area (Which means the benefits of 7nm here have to go towards the same-clocks improved efficiency side of things as opposed to increased clocks), as well as twice the amount of data being thrown around the interconnects, that means that in order to actually attain a x2 increase would require ridiculous amounts of work when it comes to reorganising cache's and interconnect technology to avoid everything bogging down from data transfer bottlenecks, alongside massive increases in efficiency and IPC.
__________________
Electrical engineer with a passion for rambling.
Reply With Quote
  #6  
Old 06-11-18, 07:44 PM
NeverBackDown NeverBackDown is offline
AMD Enthusiast
 
Join Date: Dec 2012
Location: Middle-Earth
Posts: 15,051
Quote:
Originally Posted by WYP View Post
Remember that this is a server part and that power and thermals are a major factor. It's impressive that they got a 2x increase from 2x the cores, never mind the 4x increase in floating point.
Same as it was for first gen Epyc. So I don't see that as being a factor considering they will most likely be running low frequencies higher up in the range you go, and considering the switch to 7nm allowing for the same performance at much lower power consumption I bet they will see similar frequencies. Hence the simple 2x increase instead of more as they elected to run same power consumption. Which is probably the only option without wanting to melt the coolers.
FP is a different story considering it has native support whereas the first gen did not. So really anything is impressive on that part
__________________
The Cost of Freedom -
"A price payed gladly, in the hopes that the free, live better."
Reply With Quote
  #7  
Old 07-11-18, 03:20 AM
robbiec robbiec is offline
Newbie
 
Join Date: Apr 2008
Location: Cork, Ireland
Posts: 45
Faster memory is the key here I've been told. Throughput has been improved as has latency. The fact that in 1 generation they have improved by a factor of 2 is massive.
AMD's biggest problem will be keeping up with demand...
I have 4 EPYC servers that I can basically drop in this new chip and double my compute (well I'll probably have to swap out the RAM too for faster variants) - fun tomorrow at work roadmap wise.
Reply With Quote
  #8  
Old 07-11-18, 11:36 AM
WYP's Avatar
WYP WYP is offline
News Guru
 
Join Date: Dec 2010
Location: Northern Ireland
Posts: 13,534
Quote:
Originally Posted by robbiec View Post
Faster memory is the key here I've been told. Throughput has been improved as has latency. The fact that in 1 generation they have improved by a factor of 2 is massive.
AMD's biggest problem will be keeping up with demand...
I have 4 EPYC servers that I can basically drop in this new chip and double my compute (well I'll probably have to swap out the RAM too for faster variants) - fun tomorrow at work roadmap wise.
I'm fascinated to see how well everything works in practice. The whole memory/PCIe locality stuff will 1st Gen EPYC will go away with Zen 2. I'm very interested in seeing how good memory latency and core-core latency etc is when it has to move through one die to get to another.

TBH, the I/O die is massive, which makes me think that AMD has added some kind of L4 level cache to the chip. It will be interesting to see if the same design moves to mainstream desktop parts.

This chip design is a real slap in the face for Intel, especially after their 48-core announcement, which is basically just two Cascade Lake-SP processors on a single package with the same UPI interconnect as a dual-socket Cascade Lake-SP server.
__________________
One of these days I'll change my name to Mark Bench
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump










All times are GMT. The time now is 11:49 AM.
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.