It's the product as a whole. If you isolate individual parts of PCs and SGIs, you'll find that they do have things in common. However, it's when you put those pieces together as a whole do SGIs really shine.
SGIs are built from the ground up for high performance number crunching and visualization. This can range from editing/vfx, to CAD/CAE, FAE simulations and even to weather and 'whole earth' modelling. All this can be had with one box (an Octane, Onyx, Origin, or any member of the SGI family).
To get this same type of performance on a PC, once would have to cater specificially to a certain type of application, and even then, you'd still be limited by the restrictions of the hardware. SGI, just like Apple, is a hardware solution.
Here's an example. Since we're on a visual effects forum, I'll stick with compositing. If I wanted to composite HD footage, what would I use? I could use a PC, SGI, or Apple box. Let's narrow it down. I want maximum resolution. All these boxes do that. I want speed, and I have deadlines that are same day. Ok, all these boxes can do that do. I want realtime interactivity and 99% uptime. Hmm. narrowing the field.. I think an SGI would fit the bill.
It's got a wide bus architecture, unlike a typical PC or Apple bus.
Apple, their top of the line G5.
The Power Mac G5 comes with three PCI-X slots, giving you the benefit of the newest advance in PCI technology. The PCI-X protocol supports high-performance PCI devices, increasing speeds from 33MHz to 133MHz and throughput from 266 Mbps to 2GBps.
PC, I'll go with an HP Itanium workstation for instance.
3 full-length 64-bit/133 MHz PCI-X
SGI, I'll go with an Octane2, since it's their current workstation.
Octane2 products also support the Peripheral Component interconnect (PCI) expansion bus at 266MB per second, giving you access to a wide range of network and I/O adapters. This is in addition to SGIs patented crossbar architecture which ties CPU/RAM/IO and HD together.
Graphics? What do we have available..
For both PC and MACs you can use AGP 8x compatible video cards.
I'll settle on something highend, like a NVIDIA Quadro4 980 XGL.
For an SGI, it is ingrained in the Octane2. Called V12: 128MB graphics memory, including up to 104MB texture memory.
Hard drives? All three systems can take the same HD.. U320 disks in an array.
Hmm. What else is there... Not sure.. Here are the pages that I used for this little clarification..
HP Workstation zx6000
Power Mac G5
SGI Octane2
Again, it's the product as a whole that counts, and the usability over time. You can buy a nice Octane on ebay, and it will keep up with PCs of today depending on the application you throw on it. Not only that, those Octanes are at least 2 years old. Try running a PC from two years ago and comparing it again now!
I think SGIs biggest selling point for their workstations is their unified architecture. Taken from SGI's website, this is an explanation:
Instead of competing for a shared bus, an ideal computer would allow every element of the computer to directly communicate with every other element using a private line that runs only between those two elements. This would allow the data transfer rate to be dramatically increased. It would also make the data transfer extremely predictable, since the connection between processing elements is not shared. This predictability would allow a stream of data, such as video playing off a disk, to avoid the risk of being interrupted by another random process such as the arrival of an e-mail. The challenge then becomes how to take the individual one-to-one links between components and turn them into a complete system. The answer to this problem is the crossbar switch. A crossbar switch uses advanced packet switching technology to route messages directly from one processing element of the computer, say the CPU, to another element such as the graphics system. A true non-blocking crossbar allows multiple streams of data to flow independently from one point to another; they will not interfere with or block each other. The OCTANE workstation from Silicon Graphics incorporates this kind of crossbar switch in its system architecture. The heart of the OCTANE workstation is built around an eight-port non-blocking crossbar.
The OCTANE workstation makes use of dedicated hardware processing elements to optimize the performance of key computing tasks such as graphics processing or video compression.
www.sgi.com/products/remarketed/octane/ent_wp.pdf
I hope that explains a bit, and hopefully doesn't faze you! If you've read this far.. Here.. Here's a
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