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eGPU rendering - Razer Core X chroma review

Updated: Jan 18, 2021

eGPU – external render device via thunderbolt port

I got this to aid my rendering for videos, the fractals, but others might also find this interesting if for gaming.

Why eGPU - being new to mandelbulber I’m slowly learning and in doing my first lengthy render in 4k I saw the need to improve render capacity and saw talk of ‘render beasts/farms’. My situation is that I work from a HP Zbook laptop workstation, it’s new and hi-spec (i9 & 32Gb ram) and I didn’t want another workstation set up, so I needed to add to this. I use the laptop for my work in civil engineering design (laptop as I have my own company that locates me to major design offices around the UK, so I need it mobile). I use a range of Autodesk products (AutoCAD etc) that themselves can require rendering options, and on very big individual models (rather than 100s of frames), which is my foremost choice motivator in the eGPU, with Mandelbulber having spin off benefits from it. So this eGPU might not be the best option out there for everyone but it is what best suited me and maybe so for some others

Mistakes – I first read it as a 3 slot eGPU and my lack of knowledge (and envy at Mr Sinks multi card render beast) thought that meant slots for up to 3 cards. Wrong. One card only. It seems all eGPUs like this are for the much bigger gaming market rather than design/art, so stacking cards isn’t a concern. So I had to send back the first basic Nvidia P4000 card and I hunted down a reduced price Geforce RTX 1080 Ti, which had pretty good rendering reviews. My laptop card is a Nvidia Quadro RTX 3000.

Problems – first problem was getting the damn Core X even recognised on the thunderbolt port, despite it being marketed as ‘plug and play’. My personal experience was that this was the least plug and play device I’ve ever had! Many blogs on the matter showed I wasn’t the first to find this out. Razer support was about as much use as a chocolate fireplace tbh. All they suggested was that my thunderbolt port wasn’t set up for graphics. Tbh I didn’t even know that was a thing but, if true, something to check before buying an eGPU. Contacted HP and yes ports were set up for graphics. The product comes with software called ‘Synapse’, which is as much use as a Donald Trump promise. All I saw was that it changes the colours of the Core X lights, and gives no help in setting the eGPU up, but also was told by my security software that it was malicious on bootup, so some sort of data exporting going on. Blog advice to get eGPU working was update all drivers, bios settings and a range of other things (remember ‘plug and play!?). After about 6 hours of setting changes and reboots, my laptop’s ‘thunderbolt control centre’ recognised the eGPU …but Synapse didn’t, still said nothing attached! wtf?? My laptop sees it but the dedicated software doesn’t! More blog reading and finally found one that said an error and you had to uninstall synapse, delete dirs. left after uninstall (!?) and reinstall. That worked! Finally, my eGPU worked, tested a MB render and it flew …only to find another problem…

Graphic drivers – in my ignorance I thought the drivers could either sit in parallel in windows or in the Core X. Wrong. After I got the eGPU running my laptop RTX3000 was no longer functional. Not sure if this is windows’ or Razer’s error but the latter certainly doesn’t warn you of it. Windows only wants one graphics card driver. While the 1080Ti is via Nvidia there aren’t any Geforce and Quadro drivers that work together. In theory I could have stuck with what I had but if I took my laptop to work I’d need to reinstall the Quadro driver and then do all the set up for the eGPU when back home, and tbh it wasn’t always a seamless process either. Also I wanted to be able to use both eGPU and RTX 3000 for rendering at the same time. So I had to return the 1 GeForce 1080Ti and buy a Nvidia Quadro RTX 5000, having researched a driver that works for them both. That did the trick …except …next problem

Bootup – My laptop won’t boot up with the Core X connected and switched on. It’s a thunderbolt port issue that might be unique to HP. Bootup appears to see the device as something else but can’t find it, because it isn’t that something else, and hangs on a blank screen. HP bios setting is very secure but doesn’t allow a change to stop this, like changing bootup order (reported to HP and again not the first to find this problem). It is a) annoying and b) there are occasions that on boot up windows hunts an RTX driver update that doesn’t suit the RTX 5000, so I have to reinstall the one that works for both. Pain!

However – it does work and as I type this I’m rendering on both cards and my render times have improved 2.5-3 times faster and the Quadro 5000 is set up as a very accurate pro card with 16Gb ram, so will be excellent for my big file CAD work (which will involve using the 3DS max I have in my Autodesk package – more software to learn!). I’m now running my second monitor off it. One thing to note the thunderbolt connecting lead is pretty short (0.5m) so as not to impact on the transmission rate apparently. So maybe the frustration and many lost hours of my life setting the thing up will be worth it? Hopefully this will help others to be better prepared than me and have less woes.

Summary: It’s pretty cheap, £300/$300 ish Check thunderbolt ports are set up for graphics If windows, get a card that can have the same driver as your host one if you wish to use both cards. It maybe some more IT savvy people might think of better workarounds for some of the above issues, happy to be educated!

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