Spec me: 4U rackmount setup for broadcast video

LuckyBenski

LuckyBenski

LuckyBenski

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Hi all,

We're building a rig at work to handle generation of TV signals for testing. It's going to (eventually) decode 6-8 multiplexes from the broadcast feed, modify their contents and play them back out via a PCIe modulator card. The manufacturer of these cards has recommended as a guideline:

- Recent i7 or AMD equivalent CPU (I'm thinking 8700 non-k unless the Ryzen 2700x is significantly cooler-running)
- 2x PCIe 3.0 slots (I think they're both only x1 bandwidth). 2 more x4 slots may be needed in future but hopefully not, depending on how well the initial build meets the reqs
- 2-4 drives, ideally SSDs. Could do 2 SSD and 2 HDD for backup/long term storage
- "Plenty of memory"/minimum 16GB. So I'd say 32GB may be enough, 64 max
- 4U rack space is available, up a depth of about 45cm. I could squeeze another 5cm out if I move some bundles of cat6 but it's best left alone.

It will be going into a small server room so noise isn't an issue and air conditioning is present, but I'd still like to build it as a reasonably cool/quiet machine for testing and best practise. So a decent air cooler would be appreciated, and maybe even a sensible case for fans. I won't be putting water in my server room.

Budget for the project is quite large but most of that will go on the specialist cards so I'm thinking £800-1000 as a ballpark. Pretty open to suggestion here though.

WWOcUKD?
 
Thanks folks

- Won't be used for "live streaming" as such, it will be shoving out 100Mbps+ via RF (not LAN) strictly into our office for testing. Our business is in testing TVs and apps, but we won't be serving anything to the outside world. We have partners and cloud services etc for that.

- It really will be for testing only, as far as I can envisage. We wouldn't be allowed to mess with the real broadcast environment! While it's pretty ambitious, it's largely for proof of concept regarding how TVs will behave with 100+ channels loaded.

I take your points about using real server gear. Ultimately it will almost certainly run Windows and use PCIe cards, so I figured self-build would do. Do you have much knowledge about typical pricing? Will look into DL380s :)
 
Vince said:
You are of course spot on! the g10 wouldn't even fit in the space I dont think. G7 or G8/G9 would be a decent bet but again dont think they would fit. Seems odd doing something like this on a self build but you goota work with what you have I guess :(
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Well TBF the project doesn't require server level power, a desktop PC would do fine. Up til now we've driven the modulation/demodulation hardware from laptops or Lenovo USFF boxes. It's mostly going in the server room as that's where our antenna feed is, and no one has desktop PCs - all hotdesking laptops.

It's unfortunate to be a bit blind how much resource I'll need going from 2-3 multiplexes to 6-7, but I'm assured an i7 is good enough. We don't have much actual computer hardware in the server rack either, it's largely switches, patch panels and other bits of broadcast gear. I think there's one actual computer/server in there, a file server no one uses.

I'll definitely look more at the server gear if only because wedging an ATX motherboard into a 4U tray feels crude!
 
Vince said:
There must be some sort of half rack mount server that people do. I'm only thinking about the possible aggravation later when something goes wrong and then it's almost always "Person X built this so it's person X that must fix it when it all goes pear shaped" at least with a server it takes that aspect out of it and also you get the support of the manufacturer. As you say that something pretty low spec will do the job, sort of workstation level hardware in a rack mount case.
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You're spot-on with that. We're a small team doing several weird projects so there's a lot of "How does this work?", "Oh xxx can change the settings for you". Actually my plan is to build a very user-friendly suite of tools for this project, but I hadn't considered the hardware maintenance.

Looks like a Z series workstation might come in at similar cost to what I specced up, but with solid support and product design compared to a random chassis. I'll have to weigh up the niceties like RAID storage against the reliable branding.
 
Right, here is what I've put together. If it gets pushed back to me I could shave off the second SSD and half the RAM to bring us down to about 1k, but I'm fairly happy. I expect we'll need more (bigger) storage drives if the proof of concept comes off well. Any comments?

I'm currently doing some tests to see if our tasks scale well - taking the re-processing task I apply to a single bitstream, and running it in 4-6 parallel tasks. So far it looks like it's single-threaded per task so scales OK to a point. Core count may become important at 6-7 streams and input plus output. IPC will help but I'm testing on a laptop (i7-7500U) and a USFF (i5-4570s) so we can assume a serious bump going to proper desktop CPU. My gut says an i7-8700 will do better than a Ryzen 2700 but I could be swayed.

My basket at Overclockers UK:
Total: £1,378.93 (includes shipping: £13.20)​
​
 
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