Asus Strix X299-E very low SLI scaling after going from X99 to X299

[xarot]

I posted this question on NVIDIA forums too but perhaps there's a chance someone else might have the same issue. I cannot tell if this a UEFI or driver problem?

I have a strange problem with Strix X299-E motherboard and SLI with the latest NVIDIA driver 384.76 (actually, with any driver but the X299 platform is brand new and hit retail around week ago so I guess this is the correct to use).

The thing is, SLI scaling is only around 45 % to 75 %, usually sits around 60 to 66 % per card only. The 1080TI cards and PSU have been working perfectly fine on old X99 before I swapped the motherboard and CPU. Everything else is the same. I have tried Windows 8.1 and Windows 10 to no avail, changed all UEFI settings, checked PCIe lane speeds, tried HB and single SLI bridges, disabled G-Sync, disabled V-sync, changed game settings, disabled antialiasing, updated UEFI, changed motherboard voltages and what else. Nothing else to try I guess.

Only some titles like Metro 2033 seem to work somewhat normal, the rest don't. Even Fire Strike 1.1 doesn't but then again Fire Strike Ultra does? In Fire Strike 1.1 combined test the scaling is around 35 % per card and the scores are way off.

Setup:
i9-7900X
Asus Strix X299-E motherboard
64 GB DDR4-3200 MHz (yeah, a single kit, CMD64GX4M8B3200C16)
Asus Strix 1080 TI OC SLI
Asus motherboard bundled HB bridge
Corsair AX1500i
Asus PG279Q G-Sync

[Korth]

The (X299) chipset is still very new. And it was rushed to market, months ahead of Intel's initially "leaked" roadmap/schedule. There are always teething pains and unforeseen bugs on every first-gen platform release. (Low-power/sleep/shutdown faults, RAM compatibility issues, broken RAID, USB bugs galore, PCIe/SLI problems, M.2/NVMe worries ... all the usual sorts of stuff which eventually become evident and get fixed up, lol, and only made worse every time Microsoft pushes out a new WinOS version.)

And - as with any other OEM mobo which implements nonstandard (non-Intel) features/extensions/functionality - your X299 may require firmware fixes from the OEM (ASUS) before "proper" functionality is realized. Blanketed within the usual "Increased stability / Increased compatibility / Increased performance" BIOS notes, lol.

X99 and Z170 required a bunch of BIOS revisions, some NVIDIA driver releases, and countless Win10 driver updates before "everything just worked". X299 is just starting the cycle, lol, even AM4 stuff is slightly ahead. Just hope that ASUS can keep up with supporting all their existing i100/i200 mobos, upcoming i300 mobos, X99/X299 mobos, existing AMD mobos, upcoming AMD mobos, enterprise and consumer and gamer markets alike ... lol they'll be very busy debugging and supporting this glut of new chipsets/firmwares, and they're not making it easier for themselves by offering one or two dozen mobo variants for each generation.

[Menthol]

I don't know why you have poor sli scaling for sure, but if you read X299 reviews there are issues related to poor gaming performance due at least partially to Intel's specs, not owning this platform yet I can't do any testing myself but if you read some reviews you may get some tips to help, run Windows high performance power plan while gaming may help, bios settings to keep your CPU from downclocking may help at least in gaming in general, please come back and share your experience if you get this resolved

[xarot]

I don't know why you have poor sli scaling for sure, but if you read X299 reviews there are issues related to poor gaming performance due at least partially to Intel's specs, not owning this platform yet I can't do any testing myself but if you read some reviews you may get some tips to help, run Windows high performance power plan while gaming may help, bios settings to keep your CPU from downclocking may help at least in gaming in general, please come back and share your experience if you get this resolved

That's what I've read and seen from performance perspective on single card too, that the performance is not very good in games in comparison to BW-E. I tried high power plan already but it didn't help. I think I tried those UEFI settings for power already but I don't recall exactly what settings I tried, most likely LLC and Cpu Current Capability. Temps are not really an issue in games.

Are you going to try X299 out?

[Silent Scone@ROG]

SLI performance will take a hit until NVIDIA release a fully supported driver. No different to any other launch thus far.

[LiveOrDie]

SLI on pascal is a waste of time and X299 is a waste of money for hardly no gain.

[xarot]

SLI performance will take a hit until NVIDIA release a fully supported driver. No different to any other launch thus far.

I really hope this is something NVIDIA can and will fix.

SLI on pascal is a waste of time and X299 is a waste of money for hardly no gain.

Yeah, after Pascal release I saw SLI taking a nosedive into the ground but now it is not working well anywhere. Titan X Maxwells were pretty good in SLI.

I still have my 6950X/RVE10 and I can always go back. Maybe I will. It's just that I live in a small country and selling these things is very frustrating.

[LiveOrDie]

I really hope this is something NVIDIA can and will fix.



Yeah, after Pascal release I saw SLI taking a nosedive into the ground but now it is not working well anywhere. Titan X Maxwells were pretty good in SLI.

I still have my 6950X/RVE10 and I can always go back. Maybe I will. It's just that I live in a small country and selling these things is very frustrating.

Yeah i really wanted to move to a i9 but after seeing they don't clock well without delidding and most of them cant push past 4.8Ghz it puts me off upgrading as i wanted to for the overclocking a nice 5.2ghz overclock would of been nice lol.

[Menthol]

SLI on pascal is a waste of time and X299 is a waste of money for hardly no gain.

That may be more true than false, performance on the X299 platform will improve over time for sure, Intel's sales rely on it, sli may or may not improve by much, it depends on if it's profitable enough for Nvidia, re sellers can't keep cards in stock as is and it is so game dependent

[Vlada011]

SLI on pascal is a waste of time and X299 is a waste of money for hardly no gain.

X299 is not so bad at all. Nice single threaded performance, nice ROG motherboards will show up soon.
Only whole picture is not so nice because Intel used thermal paste.
But because high Turbo clock anyway no place for some huge OC.
If someone have enough money and chance to find i7-7820X or i9-7900X on Silicon Lottery with replaced paste, they use MX-4, Gelid and Grizzly, stable on 4.8GHz example that's pure win.
Skylake X on 4.8GHz is like Broadwell on 5.0GHz plus amazing memory results near 100.000 MB/s.
It would be much better without thermal paste. i7-7820X have only 28 PCI-E lanes, but PCH have 24 more.
I understand that X299 not worth for people with i7-5960X or i7-6900K, but upgrade from other models is very nice upgrade.