Can't get 10Gbit speeds on Intel X550-T1

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SimpleTech

New Member
Aug 8, 2016
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Hey everyone, I bought an Intel X550-T1 on eBay and tested it only to find out it craps out at around ~326MB/s (2.6Gbit/s). Thinking it may be my Ethernet cable (50ft CAT5e), I swapped it for CAT6 but atlas that did not help. So I tried putting the card in a separate computer with a different CAT6 cable and that did nothing.

I also ran Iperf3 on my client computer and server which has a SolarFlare SF432 (dual 10Gbit SPF+) and I'm getting roughly the same speeds as before ~3.15Gbit/s. So what gives?

Server:
Intel Xeon E5-2683 v3
MSI Gaming X99A GODlike Gaming
64GB (4x16GB) DDR4 2133
110TB storage
Seasonic FOCUS Plus 750W
NAS4Free (latest build)
SolarFlare SF432

Client:
AMD Ryzen 7 2700X
ASUS Strix Gaming B350-F
16GB (2x8GB) DDR4 3200
HP 1TB EX920
GTX 1080Ti
EVGA 750 GQ
Windows 10 Professional x64 1803
Intel X550-T1

10Gbit switch: MS510TXPP (says both computers are getting 10G Full Duplex)

I also have another computer with a SolarFlare SF432 that I have directly connected to my server and it gets the full 10Gbit/s speeds.
 

i386

Well-Known Member
Mar 18, 2016
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Are you using windows?
Try NTttcp (with multithreading) instead of iperf and post the results please.

Edit: i should read the whole post before posting :D
 

fohdeesha

Kaini Industries
Nov 20, 2016
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fohdeesha.com
Had this same issue and it turned out to be a counterfeit intel card (also from ebay). if you need to mess with jumbo frames and other crap on a modern computer to get ~8-9gbps in iperf, something is horribly wrong
 
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SimpleTech

New Member
Aug 8, 2016
12
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3
36
Had this same issue and it turned out to be a counterfeit intel card (also from ebay). if you need to mess with jumbo frames and other crap on a modern computer to get ~8-9gbps in iperf, something is horribly wrong
Yeah it looks like it's a counterfeit. I hooked it up to another Windows machine and ran Iperf and also tried NTttcp and it still was coming under 5Gb/s. :(

Looks like I should have just opted for the ASUS 10G card.

EDIT:

UPC is showing X550-T2, yup fake.
 
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