The practicalities of a dual machine

[Matt Sugden]

So following on from a previous thread about rendering machines. I have 4 Intel Core duo 3.4 machines, who's performance has always been underwhelming, and I want to perhaps upgrade to dual socket quads as I dont want any additional boxes in my office, but I have some practical questions I need to know the answers of.

• Do I need a special version of windows to run a dual socket machine
  
• Do I need a massive PSU for a dual machine
  
• Likewise do I need huge amounts of cooling
  
• will I be paying a mssive premium for a dual socket machine over say a pair of Qseries quads or i7s
  
• similarly am I likely to see at least twice the performance with a dual socket machine compared to a similar spec'd pair of single socket machines.
  
• would a dual socket machine require less bandwidth on my network than a seperate pair of singles.
  

 

Essentially, by replacing machines I really want to capitalise on their footprint replacement by swapping them with something comparitively a lot quicker, but cost effective at the same time. For instance I built a pair of quads last year for about 600 pounds for both, so I'm just not sure the extra cost of a dual socket really is worth it, last one I spec'd up was 1300 quid.

[ihabkal]

I will answer:

1- Home versions of windows won't show and use multiple processors. Get Xp Pro or Win 7 Ultimate

2- Yes and no. a second cpu could use around 130W more, so instead of a 400W for a single socket, a 550W is needed. but you should get 650W plus to allow for future expansion, if you have multiple hard drives, many sticks of ram, sli or crossfire. there are online calculators for that

3- the dual socket machines come in bigger cases that have a lot more fans, you will get bette cooling without you doing anythign special.

4- According to my calculations GHZ per GHZ it is the same, the premium you pay for server grade components you save by not needing twice the ram, two hard drives, two cases, two power supplies.etc.... but you will save in space and electricity and software licenses

5- you will see a bit more than twice the performance in vray rendering

6- yes, and ethernet adapters integrated into server motherboards are much much better than in regular single socket motherboard, so you will also see improvement there. most of them have two adapters so you can connect to the network and to the internet via DSL without needing to add a card or to two separate networks.

 

they are not quieter. unless your cureent machines are old and the fans are old and out of alignment so they get noisy. newer cases are better these days in this area, but you need a quality case.

[AJLynn]

Ihab's got the idea. Yes, the hardware is expensive - twice as expensive, maybe more. But you don't need the multiple boxes, and you can put all the power in one box, which can be an advantage particulaly with tasks like test renders that don't farm well. Also, you use less office space and less power - and if you use air conditioning, less of that too. Yes, make sure you have plenty of power and cooling.

 

For the OS, you can use Windows 7 Professional, which is probably the best for a business environment. Make sure to get the 64-bit version.

[Matt Sugden]

So having done some calculations last night, it would seem that the dual processor route is not cost effective for my business yet.

 

This is the calculation I made, I currently have 20procs split over 3quads, 4 duos.

 

By purchasing a dual socket machine to replace a single socket duo machine I would gain an extra 6 procs overall, for a cost of £1,300.

However, by upgrading my 4 duo machines with single socket quads, I would gain 8 procs, for the smaller cost of £1,000, and this may even be less if I can fit them in my old duo motherboards. So on reflection, aside from the power savings, it just doesn't make sense really, unless I'm missing something?

[Grohu]

So having done some calculations last night, it would seem that the dual processor route is not cost effective for my business yet.

 

This is the calculation I made, I currently have 20procs split over 3quads, 4 duos.

 

By purchasing a dual socket machine to replace a single socket duo machine I would gain an extra 6 procs overall, for a cost of £1,300.

However, by upgrading my 4 duo machines with single socket quads, I would gain 8 procs, for the smaller cost of £1,000, and this may even be less if I can fit them in my old duo motherboards. So on reflection, aside from the power savings, it just doesn't make sense really, unless I'm missing something?

 

If you add two hyperthreaded Xeons you will get 16 cores from one system not 8. I am not sure about this so don't hold on my word but if you are using older style duo's you'll need a new motherboard to fit let's say hyperthreaded i7's. Your 20 core setup right now is spread around 7 PC's, one more Xeon setup and you're up to 36 cores. No matter how you look at it that's a significant jump and if you are using apps that use hyperthreading that would be the best choice in my opinion.

 

If you go with 5520's and get the ASUS Z8NA-D6C Dual LGA 1366 Intel 5500 motherboard you can use ATX case, PSU, GPU and memory to lower the price on components. No need for server grade stuff. Only thing you have to remember is limited space so just go with the regular intel fans for the CPUs. They work great and fit like a glove.

[AJLynn]

No no, HT doesn't give you extra cores, it only pretends to. The actual gain isn't 100%, it's more like 20%.

 

However, one i7 core is worth more than one Core 2 core. For example, in the Tom's Hardware CPU chart, the 2.93GHz i7-940 quad test system rendered the 3DSMax test scene in 155 seconds. The 2.93GHz Core 2 Quad QX6800 took 217 seconds.

[Matt Sugden]

yeah the tom's hardware tests are useful, I think for price/performance I'm leaning towards the i5 750 chip. I can get them up for 150quid each, and they will already out perform my Q6600s, Which have been fantastic processors for the cash, so this seems good enough for me I think.

[AJLynn]

When you're talking about machines for farming, the comparison you need to make isn't between the costs of the CPUs, it's between the total cost of the entire machines (plus whatever estimate you can make of lifetime energy and other costs). This will depend a lot on how much power you want to buy; you'll need to run your own numbers.