High Core Xeon for Gaming

Avalon · 22 Sep 2019 at 02:27

Intel have made a number of undocumented SKU’s for Amazon/Google/Facebook etc. with specific tweaks to thermal/turbo/core count. You’ll usually find them popping up on auction sites and/or the usual eastern equivalents. If you have a board that will recognise them, they can be decent buys.

As to gaming on Xeon, single core performance is and always has been the driving factor in gaming, in the old days when a Xeon was just an i5/i7 with very, very minimal tweaks, it was often cheaper to source a used Xeon, especially an QS or ES, with the newer chips and the fact a used Ryzen chip/board is for next to nothing now, it’s a different game. You can pick up a R1700 for £80+ and top end x370 boards seem to be doing £60-80 with a clear upgrade path down the road, the used Xeon/HEDT side of things makes less and less sense unless you specifically require way more cores.

Rroff · 22 Sep 2019 at 03:12

Avalon said:
If you have a board that will recognise them, they can be decent buys.

Generally they still work (and same of Xeons on desktop boards in some generations) but sometimes you get some really freak problems that are impossible to solve like some really minor incompatibility somewhere that is ultimately a show stopper. In one instance with a Xeon in a desktop board it would boot up fine just grumble about microcode but 15 minutes on the dot = BSOD - the board worked with other CPUs including other Xeons fine, the Xeon worked in the original server board it came from fine, etc.

Avalon · 22 Sep 2019 at 12:47

Rroff said:
Generally they still work (and same of Xeons on desktop boards in some generations) but sometimes you get some really freak problems that are impossible to solve like some really minor incompatibility somewhere that is ultimately a show stopper. In one instance with a Xeon in a desktop board it would boot up fine just grumble about microcode but 15 minutes on the dot = BSOD - the board worked with other CPUs including other Xeons fine, the Xeon worked in the original server board it came from fine, etc.

In fairness that’s quite an unusual example and workarounds for microcode exist in modern consumer hardware. i’ve built/run probably getting on for 30 or so different Xeon’s over 115x/1366/2011/2011-3 using all sorts of boards and a wide selection of chips including ES/QS, some ES stepping chips were problematic in some respects (all worked, some had certain features not enabled, and most had lower clocks/boost clocks etc.) but generally this was known about before purchase and they all worked as expected in testing. The trick was always in choosing a suitable board with suitable BIOS. I tend to put some time into researching the stepping before deciding if it’s worth the money though, going too early is just asking for agro.

Bluntwrapped · 22 Sep 2019 at 20:14

What’s interesting is the list of supported CPUs from board manufacturers is as incomplete as the memory QVL.

Just because it isn’t listed, doesn’t mean it won’t work

Quartz · 22 Sep 2019 at 21:17

Nikumba said:
I have the oppotunity to get my hands on a pair of E5-2686V6 Xeon so would be 36c/56t with base clock of 2.3 GHz with a turbo burst frequency of 3 GHz for a single active core, or 2.7 Ghz for all cores and some 2400Mhz DDR4

Don't bother with more than one. Unless you want two PCs, of course, or they're REALLY cheap so you have a spare in case you drop one (see video). You'll get decent gaming performance which will improve as games become more core-aware. You'll also be able to run more stuff in the background without affecting game performance.

This video may be of interest:

That said, you may find that the motherboard costs a lot.

MrPils · 23 Sep 2019 at 11:02

I have an E5-2686 v3 (18c 36t) firmware hacked for additional turbo bins. 3.5ghz 9 cores enabled was the fastest config, the main problem was stutters and the low fps drops, these became much more pronounced when increasing core count and reducing clocks (PUBG tested only). The v4 will be around 10% faster than the v3 in IPC and dual cpus will let you run them in 9+9 core mode so that all cores boost to maximum turbo, but 3ghz is just not enough for smooth and responsive gameplay (slower than my v3 @ 3.5ghz).

My R5 3600 blows my 2686 v3 out the water in gaming in every possible metric, its a bloodbath.

Rroff · 23 Sep 2019 at 18:03

MrPils said:
I have an E5-2686 v3 (18c 36t) firmware hacked for additional turbo bins. 3.5ghz 9 cores enabled was the fastest config, the main problem was stutters and the low fps drops, these became much more pronounced when increasing core count and reducing clocks (PUBG tested only). The v4 will be around 10% faster than the v3 in IPC and dual cpus will let you run them in 9+9 core mode so that all cores boost to maximum turbo, but 3ghz is just not enough for smooth and responsive gameplay (slower than my v3 @ 3.5ghz).

My R5 3600 blows my 2686 v3 out the water in gaming in every possible metric, its a bloodbath.

I'd have to look into the specifics but I think with that CPU you'd have to be able to disable specific cores for optimal results (not just due to the ring bus) and disabling the wrong ones would result in a some pretty big cross core latency scenarios. You probably also need to tune the RAM with the right balance of latency and frequency for gaming use otherwise bad things can happen.

pandem0nium · 24 Sep 2019 at 09:07

The single socket E5 1XXX V3s I believe have an unlocked multiplier and can be overclocked. Same socket.

darket · 24 Sep 2019 at 20:08

pandem0nium said:
The single socket E5 1XXX V3s I believe have an unlocked multiplier and can be overclocked. Same socket.

They are, but are at the very low end of xeons , max of 6 cores and 12 threads , bit pointless.

darket · 24 Sep 2019 at 20:14

My mistake , a E5 - 1680 v3 if you could pick one up cheap could be a bargain.

MartinPrince · 24 Sep 2019 at 21:35

darket said:
My mistake , a E5 - 1680 v3 if you could pick one up cheap could be a bargain.

They are nearly as rare as rocking horse poo and would set you back ~£300 should you find one. At that price you are much, much better looking elsehwere.

Rroff · 24 Sep 2019 at 21:40

MartinPrince said:
They are nearly as rare as rocking horse poo and would set you back ~£300 should you find one. At that price you are much, much better looking elsehwere.

This has been my problem - I'm in no hurry to move on from my current setup and having multiple i7 systems I can generally spread out work rather than relying on lots of cores on one system as things stand - but if I saw a cheap higher core count Xeon I wouldn't say no to sticking it in but mostly they are at prices where I either might as well put the money towards a newer platform or £LOL.

MrPils · 24 Sep 2019 at 22:52

Rroff said:
I'd have to look into the specifics but I think with that CPU you'd have to be able to disable specific cores for optimal results (not just due to the ring bus) and disabling the wrong ones would result in a some pretty big cross core latency scenarios. You probably also need to tune the RAM with the right balance of latency and frequency for gaming use otherwise bad things can happen.

2133mhz max memory frequency on the v3 generation, it went to 2400mhz for v4. Leaves very little room for tuning when the chipset shows no gains below c7 and secondaries and tertiarys are already at minimums. I only saw latency penalties when using an even number of cores (R5E) for whatever reason. v4 gen may be more picky as thats when the new turbo stuff came in. Also HT on or off didnt effect the turbo bin on the R5E, but using -50mv vtt and vcore shifted everything one bin further. Still a really solid platform for anything except gaming. Had my cpu on ebay for months with no takers, these things just dont sell since the spectre mess.

Rroff · 24 Sep 2019 at 22:57

MrPils said:
2133mhz max memory frequency on the v3 generation, it went to 2400mhz for v4. Leaves very little room for tuning when the chipset shows no gains below c7 and secondaries and tertiarys are already at minimums. I only saw latency penalties when using an even number of cores (R5E) for whatever reason. v4 gen may be more picky as thats when the new turbo stuff came in. Also HT on or off didnt effect the turbo bin on the R5E, but using -50mv vtt and vcore shifted everything one bin further. Still a really solid platform for anything except gaming. Had my cpu on ebay for months with no takers, these things just dont sell since the spectre mess.

IIRC 2133MHz w/ either CL8/9 was the sweet spot anyhow - outside of that tended to penalise certain tasks albeit mostly less than 1% stuff.

Tuning secondary and tertiary timings as low as they go doesn't always produce the best results - some work best as per a formula and you can get stutter from having them too low - again I've not touched this in awhile so can't remember specifics off the top of my head but stuff like tRAS and tRFC shouldn't just be tuned to minimums necessarily even if stable.

MrPils · 24 Sep 2019 at 23:50

Rroff said:
IIRC 2133MHz w/ either CL8/9 was the sweet spot anyhow - outside of that tended to penalise certain tasks albeit mostly less than 1% stuff.

Tuning secondary and tertiary timings as low as they go doesn't always produce the best results - some work best as per a formula and you can get stutter from having them too low - again I've not touched this in awhile so can't remember specifics off the top of my head but stuff like tRAS and tRFC shouldn't just be tuned to minimums necessarily even if stable.

Yeah theres various relationships to observe, though some chips just randomly chuck it out the window. Samsung B is pretty run of the mill though - TRAS is CL+TRCD, and TRFC minimum possible is 4 x TRC, though 6 x TRC is much safer and not much slower. TRAS and TRFC too low causes data corruption, it usually only shows up on long runs of HCI memtest if its borderline stable.

Ive had x58, x79, various x99 (still have two running) but couldnt quite swallow the price of x299. Ended up with a good 5960x (4.6ghz), but even that gets beaten by the r5 3600 quite handily. I got the ryzen for my SFF pc, but it was so much better gaming that i ended up replacing the 5960x with a 3800x. Pulls about a third the power of the 5960x and at 4.4ghz all core is considerably faster too. I really cant argue for the haswell-e and broadwell-e generation for gaming if buying now, when a new r5 3600 build is considerably better and comparable or cheaper in price.

Avalon · 25 Sep 2019 at 00:25

MrPils said:
Yeah theres various relationships to observe, though some chips just randomly chuck it out the window. Samsung B is pretty run of the mill though - TRAS is CL+TRCD, and TRFC minimum possible is 4 x TRC, though 6 x TRC is much safer and not much slower. TRAS and TRFC too low causes data corruption, it usually only shows up on long runs of HCI memtest if its borderline stable.

Ive had x58, x79, various x99 (still have two running) but couldnt quite swallow the price of x299. Ended up with a good 5960x (4.6ghz), but even that gets beaten by the r5 3600 quite handily. I got the ryzen for my SFF pc, but it was so much better gaming that i ended up replacing the 5960x with a 3800x. Pulls about a third the power of the 5960x and at 4.4ghz all core is considerably faster too. I really cant argue for the haswell-e and broadwell-e generation for gaming if buying now, when a new r5 3600 build is considerably better and comparable or cheaper in price.

The x58/x79/x99 was a fun ride, that ride came to a rather abrupt halt with x299, it butted up against Ryzen and more importantly ThreadRipper. I still have 3 x99 based Xeon’s and i7 servers in use, if you can bag a bargain they still make sense as the idle power usage isn’t that bad and the pricing varies wildly. The main issue is you can get an R1700 and a top end x370 board for £160 delivered, for real work that’s a lot of CPU power and cores in a 65w TDP, for games it’s not quite so ideal, but with a mild overclock, it’s still a very tidy performer for the money. The ‘more cores will be better when developers release optimised code’ argument has rarely worked - look at Titan GPU’s, they were obsolete before they were useful due to the rapid advancement of hardware and lead times on game development.

MartinPrince · 25 Sep 2019 at 13:27

Rroff said:
This has been my problem - I'm in no hurry to move on from my current setup and having multiple i7 systems I can generally spread out work rather than relying on lots of cores on one system as things stand - but if I saw a cheap higher core count Xeon I wouldn't say no to sticking it in but mostly they are at prices where I either might as well put the money towards a newer platform or £LOL.

Yes, this is the dilemma. I've seen the X79 unlocked 1680 V2 pop up a couple times recently but they still go for ~£200.

I've had the Xeon E5 2697 V2's on a dual Xeon motherboard (24core 48 threaed) and while great for fully loaded multicore work loads they really are not decent gaming CPU's. Though now even their value in multicore workloads is being beaten by the 3900X

zx128k · 25 Sep 2019 at 14:13

Once you overclock the 3800x correctly, then there is little reason to go anywhere else. See https://valid.x86.fr/j8ivxm. Also above 8 core makes little difference in many games, see 9700k vs 9900k. 9900k @ 5GHz http://valid.x86.fr/fi7tdc

Rroff · 25 Sep 2019 at 15:54

MartinPrince said:
Yes, this is the dilemma. I've seen the X79 unlocked 1680 V2 pop up a couple times recently but they still go for ~£200.

I've had the Xeon E5 2697 V2's on a dual Xeon motherboard (24core 48 threaed) and while great for fully loaded multicore work loads they really are not decent gaming CPU's. Though now their value in multicore workloads is being beaten by the 3900X

Never seen them under £300 from non-dubious sources - that is a good chunk of a newer CPU unfortunately just not worth spending on a second gen X79 setup.

MartinPrince · 25 Sep 2019 at 16:07

Rroff said:
Never seen them under £300 from non-dubious sources - that is a good chunk of a newer CPU unfortunately just not worth spending on a second gen X79 setup.

My folks live in the States and there you can buy them even now for £160. There much rarer here in the U.K. but you'd expect to pay near £200 for the 1680 V2.

I had X79 for the longest time but even at £200 I could pick up a 2700 and motherboard which would out do it by some way.