Dual processors and irradiance maps

[TRGraphics]

Does vray use both processors when calculating the irradiance and photon maps?

I'm trying to decide whether I should by a dual machine or a second computer to help with rendering. I know that you can't distribute the irradiance map accross two or more computers right now but maybe in the near future?

Tony

[Psy]

i know that if u have a proc with HT, it calcs the photon map as tho their were 2 procs.

if you have top to bottom selected, then the first proc goes from top down, and the second goes from bottom up and they meet in the center.

sorta cool to watch, really makes me wonder what a dual ht proc system would look like.

[UBIKmh]

With a dual processor you just see two buckets chasing each other. The irradiance calculation goes from top to bottom and bottom to top meeting at the middle. But then again I only have dual processor machines so I wouldn't know how it looked on a single machine.

Marc

[TRGraphics]

So apparently it does use both processors for irradeance map. So for now this is a much better choice than two computers.

Thanks guys!

Tony

[DP]

dual HT's dont render the IR map passes any different, theres just a pass starting at the top and one starting at the bottom. Wether the pass is faster with HT on i dont know, tend to use bucket mode now as it seems to be 10-20% faster.

You can distribute bucket rendering, but I tend to use the dual for rendering and another for setting up renders...works well with backburner. As far as speed goes the dual 2.8 xeon we have cuts renders from 5-6 hours to 2-2.5 hours compared with the single 2.5 machine.

[Da_elf]

ive been running a dual AMD 2400+ and its sweet. dual is definately better than 2 computers. im now going to add a dual 2.8GHz XEON to my render farm to see how nice dual HT can be

[Fermi]

ive been running a dual AMD 2400+ and its sweet. dual is definately better than 2 computers. im now going to add a dual 2.8GHz XEON to my render farm to see how nice dual HT can be

Da_elf,

The Dual Xeon will be nice add on to your render Farm.

But my advice is that you use it for Interactive work, and relegate the Dual AMD to the render Farm!
I've just got a new Dual 2,8 Xeon system and I am really really really impressed but it's interactive perormance ( as compared with a Dual MP 2000+)

While rendering the difference is as expected, what takes 150 in the AMD, takes 100 in the Xeon.

Video cards are not that different in specs, the AMD has a Nvida GF4 Ti 4800 SE and the Xeon a GF FX5600 (which was already obsolete at the purchase moment, but very vbery very cheap) I had read here and there the P4/Xeon better performance as compared to the AMDs due to the higher bandwidth, but could not think it meant that much.... Wonder how the new 64 bits AMDs will behave, they are suposed to have even wider bandwidth....

As for the Imap, it's funny, with HT on it apparently behaves as a Dual, starting simultaneoulsy from top and bottom, and although Task Manager says 0% CPU usage on all 4 CPUs it goes fast like hell, and when rendering it's so nice to see the 4 buckets chasing one after the other....

Fermí

[Junglejuz]

Are Xeons actually supposed to work well with hyperthreading? I have a dual 2.6Ghz and when i had hyperthreading enabled my machine was hanging up during rendering. It would get maybe 100 frames into an animation and then freeze. After I disbaled hyperthreading it had no more of these issues. Anyone know why?

[RErender]

We haven't had any problems with HT, maybe it is a heat issue?

[TRGraphics]

It apears that most of you think the Dual Pentium XEON is the way to go even with the additional cost over the athlon 2800.

I have not owned a pentium based computer in over 4 years, maybe I need to look at them again.

Tony

[Psy]

the amd chips have better floating point performance over most intel chips, but intel chips have a much much higher front side bus speed, which is where the discussion about memory bandwidth comes into play.

last time i checked, amd was at 333mhz and intel was at 800mhz, plus, intel is going to roll out a 1066mhz fsb when the prescott chip ships.

if i had the money to spend, i'd go with a dual p4 or xeon w/ ht anyday over an amd.

[TRGraphics]

Here is what I came up with. let me know if this setup is ok.

Antec Performance Plus Case, Model:PLUS1080AMG, Retail.
Specification:
Case Type: SOHO File Server
Color: Antec Metalic Gray
Material: 1mm SECC Steel
Drive Bays: 4x5.25" & 6x3.5"
Expansion Slot: 7
Front Ports: 2xUSB & 1xIEEE1394
Power Supply: 430W
Cooling System: 5x80mm Fans
Mainboard Compatibility: ATX
Dimensions: 20.6"x8.1"x18.6" more info-> N82E16811129115 $112.00

this is onr of the cases recommended by tyan. I am a little concerned about the 430 watt ps. Is that enough power for a dual?


TYAN "Tiger i7505" Motherboard for Dual Intel 603/604-pin Xeon Processors, Model "S2668AN" RETAIL
Specifications:
Supported CPU: Socket 603/604 Dual Intel Xeon Processors
Chipset: Intel E7505 + ICH4
FSB: 533/400MHz
RAM: 4x DIMM for DDR200/266(ECC/Non-ECC) Max 4GB
IDE: 2x UltraDMA 100/66 up to 4 Devices
Slots: 1x AGP 4X/8X 1.5V, 5x PCI 32-bit/33MHz
Ports: 2xPS2,1xLPT,2xCOM,4xUSB2.0,1xLAN,Audio Ports
Onboard Audio: Realtek ALC650 6-Channel Codec
Onboard LAN: Intel 82551QM 10/100M
Form Factor: ATX more info-> N82E16813151114 $239.00 $239.00


Intel Xeon DP 2.8 GHz 533MHz FSB, 512K Cache, Hyper Threading Technology - Retail
Specification
Model: Intel Xeon 2.8C w/ Hyper Threading
Core: Northwood
Operating Frequency: 2.8GHz
FSB: 533MHz
Cache: L1/12K+8K; L2/512K
Voltage: 1.525V
Process: 0.13Micron
Socket: Socket 604
Multimedia Instruction: MMX, SSE, SSE2
Warranty: 3-year MFG
Packaging: Retail box (with Heatsink and Fan) more info-> N82E16819117016 $339.00 $678.00


Corsair XMS Extreme Memory Speed Series 184 Pin 512MB DDR PC-3200 - OEM
Specification
Manufacturer: Corsair
Speed: DDR400(PC3200)
Type: 184 Pin DDR SDRAM
Error Checking: Non-ECC
Registered/Unbuffered: Unbuffered
Cas Latency: 2-3-3-6 1T
Support Voltage: 2.6V
Bandwidth: 3.2GB/s
Organization: 64M x 64 -Bit
Warranty: Lifetime more info-> N82E16820145416 $111.00

I already have 1.5 gig of this memory.


WESTERN DIGITAL SPECIAL EDITION 80GB 7200RPM IDE HARD DRIVE, Model WD800JB, OEM DRIVE ONLY
Specifications:
Capacity: 80GB
Average Seek Time: 8.9ms
Buffer: 8MB
Rotational Speed: 7200 RPM
Interface: IDE ULTRA ATA100
Features: High-performance with 8MB Buffer
Manufacturer Warranty: 1 year
Remark: OEM DRIVE ONLY more info-> N82E16822144122 $74.00

I have a cd+rw and floppy and 21" monitor and 4600 video.

Subtotal » $1,214.00

Tony

[KVMaster]

What does HT stand for?

When you guys are speeking of dual processors with HT turned on, What does the HT stand for?
And how do you turn it on?

[nully]

Hyperthreading - its a feature in high end pentium 4 chips http://www6.tomshardware.com/cpu/200..._306ht-20.html

[Da_elf]

problem with HT is if you have dual HT your option is windows XP since 2kpro doesnt support 4 processors. however. has anyone ever tried it with win 2k server or advanced server?