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Old/Unititled Conversations
I removed the information that Apple use MXM in their new iMac 24" and only use PCIe in their Powermac line of computers. While interesting for a Mac-user, it's quite pointless information in this article. 81.233.73.177/Jonas
PCI-Express is not, however, fast enough to be used as a memory bus.
First, I think you mean FSB (or some chipset to chipset bus, similiar to the Intel Hub interface, or the PCI bus which glues the North and South bridges together), not "memory bus." The memory bus is handled by the Noth bridge or Memory Hub controller. Secondly, a "high-bandwidth configuration with 8 lanes allowing 8 bits to be sent direction simultaneosly would allow up to 2,000MBps bandwith (each way)..." Also "future increases in signaling speed could increase that to 8,000MBps each way over the same 40 pins." "It...can also be used to replace the existing Intel hub architecture, HyperTransport, and similiar high-soeed interfaces between motherboard chipset components." In light of this information, I don't believe the case that PCI-Express is not "fast enough" for FSB/chipset to chipset communications(?) is supportable.
- Quotes taken from Scott Mueller's Upgrading and Repairing PCs, 15th Anniversary Edition, Chapter 4, Types of I/O Buses, page 333
--MSTCrow 06:31, Jun 22, 2004 (UTC)
Apple's running a 1.25Gbps/line x 64 line bus in their latest G5's, which due to overhead and ping-ponging, delivers about 20GBps continual. That is to say the current on-market machines already outperform the theoretical performance of not-yet-existing versions of PCI-X by almost 3x. HyperTransport is even more effected by this speed issue, as it is only offered as a backplane bus, whereas PCI-X has a future as a PCI replacement (maybe, we'll see). Generally though my statement is clearly supportable even today.
Maury 12:10, 22 Jun 2004 (UTC)
When you say PCI-X, you mean PCI-Express, and not PCI-X, right? PCI-X is another PCI-based bus, apart from PCI-Express.
--MSTCrow 16:25, Jun 23, 2004 (UTC)
Yeah, sorry, my bad short form! Maury 12:04, 24 Jun 2004 (UTC)