Razer Thunderbolt 4 Cable (2.0m / 6.56ft)
As many on this and other subreddits, I've struggled quite a bit with various cables to connect my eGPU (Razer Core X Chroma). And of course, the issues were occuring whenever I tried using 2m long ones.
None of the Thunderbolt cables I bought off Amazon did the trick. I was mainly relying on CUDA-Z to confirm the negotiated speeds:
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Short cables, incl. original cable that came with the eGPU: 2100 / 2700 MBps (16.8 / 21.6 Gbps).
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Longer 2m active TB4 cables: 1400 / 1750 MBps (11.2 / 15 Gbps).
[UPD:] Corrected Mbps to MBps, this was an obvious mistake.
Max. speed expected from TB3 in data-only mode is 22 Gbps [LINK], which after division by 8 gives us max. speed of 2750 MBps. 22Gbps = 22000 Mbps = 2750 MBps.
The only 2m cable that was on par with short ones was an old Razer Thunderbolt 3 cable I found on a local used electronics market (p/n RC21-01270101-R3M1). However, this cable cannot deliver enough power to my laptop, which throttles the CPU. This was not the case with other cables, so the problem was not on the eGPU side.
Question: has anyone benchmarked Razer Thunderbolt 4 Cable (2m version)? What speeds does it actually deliver? Razer website states "40 Gbps" without even the "up to", but I have some serious doubts about its performance.
[UPD2:] Here is the info from CUDA-Z for the 4 cables that I currently have on hand. Using LG Gram (2022, Intel 12th Gen CPU) with Razer Core X Chroma and Asus Nvidia RTX 4070 Ti SUPER:
1. Razer Thunderbolt 3 cable: 2m [RC21-01270101-R3M1]
Note: purchased on aftermarket, came in original Razer box
2. Razer Thunderbolt 3 cable: 50cm [Core X Chroma stock cable]
3. Plugable Thunderbolt 3 cable: 80cm [TBT3-40G80CM]
Note: purchased on Amazon from official Plugable store
4. Cable Matters Thunderbolt 4 cable: 2m [model number on Amazon page:430315031]
Note: purchased on Amazon from official Cable Matters store
5*. Plugable Thunderbolt 4 cable: 2m [TBT4-40G2M]
I have returned this one and did not save the screenshot from CUDA-Z. However, the reason for return was due to low speed - it was on par with Cable Matters 2m cable. Originally ordered off Amazon from the official Plugable store.
I had no problems with my Cable Matters 2m certified TB4 cable. I do not use it that much. I had crashes of the eGPU before. But after replugging it has worked fine. And it delivers the 2.6-2.7 GiB/s you would expect. (I have not compared against the short original cable. I am sure there is some slight loss)
Cable Matters 2m was the first one I tried. Used it for several months until I tried some benchmarking, which showed lower scores than I expected. Then, I realized that cuda-z also showed the much lower speeds. Could be my particular cable, though. I saw good reviews of these cables before.
This one works great for me, is a nice length: [6Ft] Thunderbolt 4 Cable, Maxonar Thunderbolt 4 Cable 40Gbps with 100W Charging and 8K/5K@60Hz Compatible with Thunderbolt 4/3, USB4 and USB C https://www.amazon.ca/dp/B0BML8YD92/ref=cm_sw_r_cp_apip_OGNMfx6fgFFPw
Haven't tried this one. The 2 branded cables I used were Cable Matters and Plugable. Both did not do the job well enough.
I haven't had a cable yet that didn't work but my cable matters 6.6ft just crapped out of me. The best one I used so far is the apple thunderbolt because it fits very snugg and has very little wiggle room compared to the others.
I was looking at the Apple cables earlier. The 2 meter one (made by Belkin) is likely to deliver the full speed of 22Gbps. Have you had a chance to benchmark it or check the speeds in CUDA-Z? A screenshot would be very much appreciated.
They've also got the 3 meter TB4 cables promising to deliver the same performance, but it's a bit on the expensive side and I haven't found anyone claiming to achieve expected speed with these cables. If you've got one and could make a quick test - that'd be just great.
I use a Cable Matters 2M Active Thunderbolt 4 cable with no issues.
Not cheap but can't fault it, it just works. I will run a Cuda-Z benchmark later to confirm the speed.
Thanks, would be great to see your results with this cable. I just re-tested it and updated the post with the CUDA-Z screens for each of the cables I have. Unfortunately, Cable Matters 2m cable did not perform that well.
TBH, I also never had any issues with this cable while using my laptop. Not until I came across some posts showing the connection speeds from CUDA-Z and decided to see for myself. xD
"CABLETIME Thunderbolt 4 USB C Cable Certified 8K 60Hz HDR PD100W 40Gbps Compatible USB 4 for Macbook Dell Laptop Type C C422" 1.8m from Aliexpress - US $29.29
Thanks for sharing. This one seems to perform very well for its price.