Decision Time: Xeon W-Series vs. Gold series

[DieWurst]

Hello all.

I'm a programmer and my hardware knowledge is a tad limited. Nonetheless the configuration of the next gen. Dell Precision workstation has fallen into my lap.
The main goal is to cut down on compiling times, using Visual Studio 2017. No need for any fancy graphics card.

Coming from a Dell Precision T7810 (2x E5-2630 V3)
Our test runs showed that cores help to a certain degree, after that, more Hz per core produces more gains.
I'm looking to ditch one processor in favor of a single, faster one.

My current component selection and budget leaves me with either:

Dell T7820 (dual CPU capable) and a Xeon Gold 5118, or similar
12cores, 24 Threads, Base Frequency 2.30 Ghz, Max Turbo Frequency 3.2 Ghz
or
Dell T5820 (single CPU capable) and Xeon W-2155 (fastest option available in this chassis right now)
10cores, 20 Threads, Base Frequency 3.30 Ghz, Max Turbo Frequency 4.5 Ghz

There is a significant price difference between the two CPUs, on paper they do not look too different.
There's also a price difference in the chassis, the T5820 being the cheaper one.
I could upgrade the SSD from 512GB to 1TB, add more memory and the like.

I'm grateful for any insight into what causes performance differences in the W-series and Gold-series & any thought on the selection. Oh, I'm stuck with Dell in case that idea comes up first.

Cheers.

 

[slashy16]

The Dell T5820 is the better choice if you don't plan on filling the second slot on the T7820. The all core turbo on the W2155 is 4.0ghz which should easily trounce the 5118 in every test.

 

[DieWurst]

The Turbo is of less importance. Visual Studio does make use of all available cores, which, aiafik, will not allow Turbo mode. It's likely reserved to run on 1-2cores only, not all ten.

It's a mystery, there are other Gold series CPUs and the ones with core and frequency numbers similar to the W-2155 cost twice as much if I go shopping for them separately.
I'd expect a big performance gain, not just added features. Yes, I'm leaning towards the T5820 as well, but the lack of Benchmarks is a bit worrying.

Edit:
I did mention the 5118, the price for that is actually somewhat en par with the W-2155.
Finding the cores and speed of the W-2155 in a Gold CPU crashes the budget in the Dell configurator.

 

[JoeRambo]

High turbo clocks are also important in day to day experience in Visual Studio and a gap of 1.3Ghz is huge. Remember, operations like project loading, plugins etc are not going to scale with more cores as they would with clocks. Given those choices I'd go with T5820.

And this gen of Intel CPUs is rather generous with turbo, in fact they rarely if ever run base clocks. You can expect average clocks north of 4Ghz

There are some not so subtle differences between those as well. Gold one has 6 channel mem and expandable to dual socket operation, Xeon W is quad. In Visual studio, i'd not worry about it, but doing things with scientific calcs, or for example some JVM loads bound by GC, now that could change things ( but then again, a gap for Ghz+ between all-core turbos is huge).

 

[slashy16]

The Turbo is of less importance. Visual Studio does make use of all available cores, which, aiafik, will not allow Turbo mode. It's likely reserved to run on 1-2cores only, not all ten.

It's a mystery, there are other Gold series CPUs and the ones with core and frequency numbers similar to the W-2155 cost twice as much if I go shopping for them separately.
I'd expect a big performance gain, not just added features. Yes, I'm leaning towards the T5820 as well, but the lack of Benchmarks is a bit worrying.

Edit:
I did mention the 5118, the price for that is actually somewhat en par with the W-2155.
Finding the cores and speed of the W-2155 in a Gold CPU crashes the budget in the Dell configurator.

Turbo is very important. The W2155 will absolutely destroy the 5118 in all tasks single or multithreaded because of it's higher clocks.

 

[Topweasel]

The Turbo is of less importance. Visual Studio does make use of all available cores, which, aiafik, will not allow Turbo mode. It's likely reserved to run on 1-2cores only, not all ten.

Seems like you have a misunderstanding of the turbo system of Intel CPU's. Yes the absolute top number is limited to light core usage (I believe in this gen is 2 cores). But the there are different maintained (assuming you have the cooling) turbo's for all levels of core usage including an all core turbo.

In truly Linear parallel computing. The 2155 even at base clocks for each of them is going to trounce them since 10*3.3 is going to be 33GHz of computing versus 2.3*12 which is 27.6GHz of computing. When you take in considering all core turbo, I don't know the numbers, but the 2115 is the LCC die and the 5118 is on the HCC die, so the delta on the all core turbo is going to be higher on the 2115. This will further push the compute power of the 2115 in the lead. Heck just the 2core Turbo of the 5118 is still 100MHz lower than the base all core clock of the 2115.

 

[Rifter]

Dell T5820 system unless you plan on dual CPU.

 

[slashy16]

(assuming you have the cooling)

I don't have a T5820 in front of me right now but we deployed one recently in the states with the 8 core W series xeon and with the cooling
by Dell the CPU never throttled.

I believe the turbo's were
1C 4.5ghz
2c 4.3ghz
4c 4.1ghz
8c 4.0ghz


The cooling included by Dell is better than most custom builds. These workstations are without equals and are absolute beasts if you have an ECC memory requirement.

 

[Topweasel]

I don't have a T5820 in front of me right now but we deployed one recently in the states with the 8 core W series xeon and with the cooling
by Dell the CPU never throttled.

I believe the turbo's were
1C 4.5ghz
2c 4.3ghz
4c 4.1ghz
8c 4.0ghz


The cooling included by Dell is better than most custom builds. These workstations are without equals and are absolute beasts if you have an ECC memory requirement.

Yeah I love the build quality of the mid and high end Precisions (the 3000 series is a joke imho). I was saying that as a generality for the tech on the CPU's and not for these systems in specific.

 

[DieWurst]

Now that is encouraging news. Thank you!

On other Precisions we have (eg T7600 to T7810) we don't see any Turbo activity during builds.
I agree that for regular activities the W-2155 will deliver better performance / feedback to the user.
On The current T7810 with dual CPUs we can already see overhead losses, juggling up o 40threads during heavy loads.

 

[Topweasel]

Now that is encouraging news. Thank you!

On other Precisions we have (eg T7600 to T7810) we don't see any Turbo activity during builds.
I agree that for regular activities the W-2155 will deliver better performance / feedback to the user.
On The current T7810 with dual CPUs we can already see overhead losses, juggling up o 40threads during heavy loads.

Watch CPU speed more carefully. All desktop chips basically will stay under load at the max turbo as cooling is less of an issue. Not seeing a clock change isn't the same as no turbo.

Also keep in mind there are Xeons without turbo.

As for diminishing returns with tons of cores. It's just one of those things you aren't going to get 40 cores worth of production. But a Dually with 40 cores is going to be tons faster than a 14c single CPU system.