View Full Version : WinXP 64bit the Toaster and Dual Core Proc

07-18-2005, 01:03 AM
With all the new interest in dual processors and 64bit Windows XP I thought to throw these question out there to see if anyone has tried this:

**Can the Toaster HW run on XP 64 bit?
**Since XP uses only 2 Processors what is the use of a dual "dualcore" cpu? 4cores total
**Does the Toaster run on Windows 2003 Server?

07-18-2005, 02:03 AM
Hi jularroyo,

First, I do not know what NT has up its sleeve but from what I understand about Win 64 OS...is that you need to have the hardware drivers in 64 bit...even if the software runs 32 bit...

So as it stands now...I don't think VT can run on the Win 64 bit OS at this time since the driver is 32 bit. But you could dual boot a system to run both 32bit XPpro and Win 64 bit...

Most of NT's software is multithreaded so the more procs the better including dual cores..


Ray Adams

07-18-2005, 12:50 PM
Win XP, regardless of 32 or 64 Bit version, is capped at two CPUs? Does the Toaster run on Win 2003 Server / 32 bit version? The standard edition of Server 2003 three supports 4 CPUs.


07-18-2005, 03:21 PM
Well, I don't know about physically, but if you have dual-CPUs in a XP system, you simply turn on hyperthreading and get FOUR virutal CPUs. No need for dual-core to get that.

Paul Lara
07-18-2005, 04:54 PM
Can the Toaster HW run on XP 64 bit?

No the underlying drivers are not written for X64, which is required for the hardware component.

07-18-2005, 05:56 PM
xp pro will support to pychsical cpus with 2 cores on each

07-18-2005, 08:41 PM
xp pro will support to pychsical cpus with 2 cores on each

So does that mean with hyperthreading on one gets 8 virtual CPUs?

07-19-2005, 04:33 PM
well i may be mistaken but i dont think dual core chips have hyperthreading per say that it shows up as virtual cpus but does allow for many process' at a time

07-20-2005, 02:26 AM
So does that mean with hyperthreading on one gets 8 virtual CPUs?
You get 4 virtual CPUs on a single dual core P4 (with HT support). Not many dual core processors support HT though. None by AMD do and only one by intel currently does.

Yes, once you get dual core xeons with HT you'll end up having 8 virtual CPUs.


07-21-2005, 01:07 PM
So is dual-core without HT really better than single-core with HT?

07-21-2005, 01:46 PM
So is dual-core without HT really better than single-core with HT?
Oh absolutely.
HT is just using unutilized pipelines of the single core to simulate a second, virtual processor/core. Since only unutilized pipelines are used, you can only expect a performance gain of 15%-20% max with highly optimized software.
With dual cores you can achieve up to 100% since they are independant of each other.
In the case of intel processors, performance of a single dual core should be on par to a compareable xeon set-up, since both have the same memory bus.
So a dual core HT capable P4 would give you an extra 100% due to the second core, and an extra 30%-40% due to both cores supporting HT. In an ideal world that is. (compared to a single core, no HT chip).

For AMDs the situation is a bit different due to the local memory access per processor (-socket), which give dual processors a bit of a bandwidth advantage compared to dual cores. Also it seems that AMD dual core processors have better cache management compared to intel dual cores.


David Curle
07-21-2005, 05:55 PM
So is dual-core without HT really better than single-core with HT?
First lets sort out a few facts.
Hyperthreading is a suedo multicore and only gives some increase in results. Some times no increase. AMD chose to not go down that path, but decided to do multi core with very good architecture. They decided to put a memory controller on each CPU. This means that for every CPU added, a memory controller is added. (read scalability)
Xeons however have to share memory and controller - this is the bottle neck in the Xeon architecture - which of course gets worse the more CPUs you add. (read crappy scalability)
XP sp2 enabled systems to see more than two CPUs and it also enabled the OS to see the extra memory controllers on the Opterons (previously only available under WIN64)
This is called NUMA. So with the Opterons you have dual channel ram on each CPU -so you must install four sticks of paired ram.
The Opteron Dual cores are blowing away the dual 3.6 Xeons on all multi threaded operations.
Note: quite a few applications have not caught up with this change in direction from clock speed to multicore, and have yet to write drivers to fully utilize the multicores.
Some operations are actually best served by a single processor with very high clockspeeds. Some encoding operations fall into this catagory. (at present)
The AMD cheaper variety- the Athlons are doing very well however- even at these tasks.
Note the AMD chips are native 64bit and will smoke along when using 64bit OS. 64bit gives more addresses and allows huge amounts of ram - not 3 and a bit GBs as XP gives you. This extra ram can allow far more concurrent threads which is good news for video.
You can see results here:

Here are some more tests also using dual Quadro 4400s in SLI for you 3D lightwave nuts!