I am building a file server slash video encoding rig and I had originally planned to use an i7 970. I want power, and am willing to spend money for it, but not for top of the line Xeon stuff. The e5645 is the bottom of the barrel of the Hexacore Xeons. How will two stack up against the i7 970? Can I rely on pre-existing CPU benchmarks to give me an idea of how they would compare in actual x264 use? The source would be offloaded to the GPU with CUDA, so the CPU would only be encoding. I am looking to get real-time speed on the 2nd pass with 1920x1080p video @ ~17,200 kbps. Right now, my i7 920 hits about 3/8 real-time at those same specs.
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Dual Hexacore Xeons (e5645) vs. i7 970
- Thread starter ramicio
- Start date
If your encoder is good enough to utilize all the threads the e5645 will be the best choice. pick up one of the 2nd hand sr-2's that are all over the for sale section and you'll be able to overclock it to ~3.8-4GHz while the 970 is unlikely to push much more than 4.4GHz.
Assuming
- your encoder is linear vs threads i.e. 4 threads is 2x faster than 2 threads (you can simulate this by half your cores in your bios, not to be confused with turning HT off)
- and 970 is at 4.4GHz
- and 5645's are at 3.8GHz
- and 920 was at 4.2GHz
Then 970 is 57% faster than your 920, but the 5645 will be 171% faster. If the 920 is 3/8 real time, you'd hit just over real time at 3.8GHz with 2 5645's. They are great chips!
Assuming
- your encoder is linear vs threads i.e. 4 threads is 2x faster than 2 threads (you can simulate this by half your cores in your bios, not to be confused with turning HT off)
- and 970 is at 4.4GHz
- and 5645's are at 3.8GHz
- and 920 was at 4.2GHz
Then 970 is 57% faster than your 920, but the 5645 will be 171% faster. If the 920 is 3/8 real time, you'd hit just over real time at 3.8GHz with 2 5645's. They are great chips!
See, here's the thing, I have no desire to overclock or use any consumer parts except hard drives (those $1,000 hard drives really are no better.) This is going to be a rack server. So this will all be assumed at the stock 2.4 Ghz.
I currently encode with 12 threads. I've seen they recommend to throw 1.5 times than as many cores (real + virtual) you have for x264, and with my 920 I've confirmed that 12 is faster than 8 and anything above 12 does nothing.
Then we have the subject of this registered memory...I've heard it's slower, but I'm not thinking this will affect video encoding.
Thanks so far!
I currently encode with 12 threads. I've seen they recommend to throw 1.5 times than as many cores (real + virtual) you have for x264, and with my 920 I've confirmed that 12 is faster than 8 and anything above 12 does nothing.
Then we have the subject of this registered memory...I've heard it's slower, but I'm not thinking this will affect video encoding.
Thanks so far!
So in this case the 970 will be 80% faster, the 5645's will be 171% faster.
There's two things for server memory registered and ecc, usually they come together but not always. Registered just means buffered, which you generally need for large amounts of memory because the IMC is loaded too heavily by the memory ECC means you have parity on your memory which means you're less likely to get errors. For 24gb it's borderline as to whether you need it, I've done it both ways and never had a problem. For anything over 24gb you'll have to get ecc/registered. So really it depends how much memory you're going to run. ECC memory is easily available at 1066 CL7 and 1333 CL9. Any faster than that is overclocking the IMC on the processor anyway so if you want to keep it stock then there's no real speed benefit to going with non ecc/registered except for price.
There's two things for server memory registered and ecc, usually they come together but not always. Registered just means buffered, which you generally need for large amounts of memory because the IMC is loaded too heavily by the memory ECC means you have parity on your memory which means you're less likely to get errors. For 24gb it's borderline as to whether you need it, I've done it both ways and never had a problem. For anything over 24gb you'll have to get ecc/registered. So really it depends how much memory you're going to run. ECC memory is easily available at 1066 CL7 and 1333 CL9. Any faster than that is overclocking the IMC on the processor anyway so if you want to keep it stock then there's no real speed benefit to going with non ecc/registered except for price.
So it will be good. Most movies aren't full-frame 1080p anyway, most are 2.35:1 or 2.4:1 and I use a lower bitrate for those anyway, so they go pretty fast. They go about 12 FPS on my 920, while full 1080 do around 9.5 FPS (second passes.) I'm only looking to run 12 GB. I don't think I will ever need more than that. I use 12 GB in my i7 920 rig without a page file and haven't even ever come close to using it all.
http://secure.newegg.com/WishList/PublicWishDetail.aspx?WishListNumber=13540331
I had already started to build it, but I ended up using the motherboard and RAM I had bought for my desktop. I had also planned to use 1.5 TB hard drives but I thought I'd feel safer to start out with 2 TB drives, and I had already bought two 1.5 TB drives. So I bought 4 of those 2 TB drives already, and an Areca ARC-1222. The case and PSU I will most likely just get off eBay. The motherboard I am always looking for open box items.
http://secure.newegg.com/WishList/PublicWishDetail.aspx?WishListNumber=13540331
I had already started to build it, but I ended up using the motherboard and RAM I had bought for my desktop. I had also planned to use 1.5 TB hard drives but I thought I'd feel safer to start out with 2 TB drives, and I had already bought two 1.5 TB drives. So I bought 4 of those 2 TB drives already, and an Areca ARC-1222. The case and PSU I will most likely just get off eBay. The motherboard I am always looking for open box items.
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Strange, I swear I had it as 2 before...
I am initially going to buy just one CPU just so I can get it up and running sooner than later. I'm almost out of storage on my 3.5 TB of my desktop drives. I'm going to be setting up the HD's in RAID 5. I'm starting with 4, so 6 TB at first should be plenty. Down the road I might experiment with a dedicated link to my desktop with 2 Intel Gbit NICs with channel bonding, and if I can afford it, I will just get a managed switch instead of a dedicated link.
I am initially going to buy just one CPU just so I can get it up and running sooner than later. I'm almost out of storage on my 3.5 TB of my desktop drives. I'm going to be setting up the HD's in RAID 5. I'm starting with 4, so 6 TB at first should be plenty. Down the road I might experiment with a dedicated link to my desktop with 2 Intel Gbit NICs with channel bonding, and if I can afford it, I will just get a managed switch instead of a dedicated link.
Hmm I would be careful which exact supermicro board you get, some have good LSI raid controllers, some have bad LSI controllers and some don't have anything. Not sure if that does it but it claims raid 5 support only in windows which makes me think it's software raid. I'd either get a different one or add a raid controller. The chassis is really nice, I've used the barebone version of it for an esxi server before.
