Fri Oct 19 16:35:19 2001
Intel’s plans concerning the new chipsets for its Pentium 4 processor keep changing. However, there is a single trend, which goes through all these changes: no more Rambus memory. In fact, Intel has already cancelled its Tulloch chipset, which was supposed to support new 4-bank PC1066 RDRAM, having replaced it with Tehama-E, a new i850 chipset revision supporting [color=blue]533MHz Quad Pumped Bus and regular PC800 RDRAM[/color]. As it follows from the last updated roadmap of Intel’s, [color=red]Tehama-E is to become the last Intel chipset supporting RDRAM.[/color]Starting from early 2002, Intel will start making DDR chipsets for Pentium 4 CPU. At first, there will appear Brookdale-D supporting DDR200/266, and then it will be replaced with its renewed modifications, namely: Brookdale-E supporting 533MHz bus and Brookdale-G with the integrated graphics core.
However, we found out that Intel is also working on a couple of really interesting DDR solutions:
Granite Bay. This chipset should appear in the middle of next year and will be targeted for high-performance systems and uni-processor workstations. [color=green]The key feature of this solution will be dual-channel DDR266 support. Using 2 64bit channels will provide 4.2GB/sec memory bus bandwidth, which will allow to load with data bus of new Pentium 4 processors supporting 533MHz Quad Pumped Bus. As for its performance, Granite Bay promises to prove much faster than i850, because due to channels interleaving the latency of its memory subsystem is expected to be extremely low.[/color] Moreover, Granite Bay will support AGP 8x interface and will be equipped with ICH4 South Bridge supporting Serial ATA and USB 2.0 interfaces.
Springdale. This chipset is expected to arrive in Q2’03 and is aimed at the new Pentium 4 processors made with 0.10micron technology. It will also support dual-channel DDR memory. In this case, however, it is very likely to be about the new DDR II, as the year 2003 is still quite far away. This chipset will use ICH5 supporting wireless LAN and 3GIO. Supposedly, Springdale will be aimed at the mainstream market sector.
[color=purple]So, now we hope no one any more doubts about the memory type of the future.[/color]
You have been informed.
First point: 'Tehama-E' may not be very attractive because having a 533MHz FSB P4 with PC800 RDRAM will introduce additional latency due to the asynchronous clocking. This is not spectacular.
Second point: 'Granite Bay', with dual-channel DDR266, mated to 533MHz FSB P4's, should be an extremely attractive high-end chipset, a worthy platform for Intel's flagship desktop processor.
We'll have to see how the competition responds. I don't think I'll be building a new system before 'Granite Bay', probably not even until later, after the AMD Hammer K8 core has been released and has some respectable platforms.
Information courtesy of Xbit Labs, all emphases mine.
[URL]http://www.xbitlabs.com[/URL]
[color=green]This message has been edited. Twice, even.[/color]
(Edited by Imitation Gruel at 9:54 am on Oct. 19, 2001)
Fri Oct 19 17:32:33 2001
Because 133x4=532.
Fri Oct 19 19:24:23 2001
from Riso posted at 1:32 pm on Oct. 19, 2001
Actually the "new" bus runs at only 532mhz.Because 133x4=532.
Unless the clock was actually 133.3333 (ad infinitum).
Then the bus speed would be 533.3333 (ad infinitum).
Just an old holdover from my Amiga overclocking days, when you'd change a 4-pin clock crystal to overclock (or underclock). Used to have clocks of 33.3333, 66.6666, etc.
Fri Oct 19 19:27:20 2001
Fri Oct 19 20:24:59 2001
In fact, Intel has already cancelled its Tulloch chipset, which was supposed to support new 4-bank PC1066 RDRAM
Fri Oct 19 22:51:33 2001
Someone would have compare the latency of PC800 running on a 400mhz bus with a 533mhz bus with the 3/4 multiplier used.
Sat Oct 20 01:23:40 2001
Sat Oct 20 02:28:44 2001
Sat Oct 20 02:29:58 2001
Sat Oct 20 02:30:34 2001
Ah well. postcount +++
Sat Oct 20 03:32:28 2001
This is different from async chipsets like the Via Apollo and i810/i815.
Sat Oct 20 03:56:31 2001
I'm hoping 1/1, but I fear 3/4.
By the way, thanks for the information.
Sat Oct 20 03:58:06 2001
Sat Oct 20 07:49:07 2001
Whats also interesting is that the SiS and Via DDR chipsets for P4 are also very low latency. Maybe it's something specific to the P4.
Sat Oct 20 08:15:50 2001
There is no signal to accept, at least not from the memory anyway. It might be slower because the memory is slower, but that's the whole point.
So, in your estimation, if you plug PC1066 DRDRAM into a 'Tehama-E' motherboard, with a 533MHz FSB Pentium 4, will the memory operate at 800MHz or 1066MHz?
My guess and fear is that it will operate at 800MHz.
Therefore I'll most likely wait for a 'Granite Bay' solution as the first realistic look at a Pentium 4. And I'd give it a few months, actually, so that the Hammer K8 core would be released. If 'Clawhammer' has some decent platforms from the get-go, it'll be up to one of the two, I suspect.
Sat Oct 20 22:40:46 2001
It will be able to run at both 1066 or 800, so it can use both types of ram, while keeping the 533 bus.
Sun Oct 21 06:06:45 2001
It will be able to run at both 1066 or 800, so it can use both types of ram, while keeping the 533 bus.
Most excellent. But I think I might wait for 'Granite Bay' anyway, because the lower latency of DDR-SDRAM should help the P4 out. SiS's 645 chipset, using a single channel of PC2700 DDR-SDRAM manages to score very close to, or utterly destroy, the i850 in most benchmarks; even with lesser and unmatched bandwidth.
So if Intel equips 'Granite Bay' with a powerful memory controller it could be a hell of a chipset.
We'll have to see how it, and the initial "ClawHammers" perform.
Sun Oct 21 06:20:57 2001
Sun Oct 21 06:34:49 2001
If this granite bay thing comes out, it will mean the death of RAMBUS as we know it.
While I might miss the RDRAM technology -- I find it interesting -- I will not miss Rambus, Inc.
In fact, i845 is already pushing it out of OEM systems, despite the loss in performance <snip>.
Mhmm. OEM's care about getting cheap boxes out to the customers. i845 enables cheap(er) Pentium 4 boxen with lots of <hick> dem' dar' megahurtses. </hick>