need a bit of help on Duals and Quads

Hi, friends
i'm just wondering which Operating systems can give higher performance for AMD Duals and Quad rigs?

I use it to do massive mathematical calcs, will win xp SP2 be good for me ?
cause i dont want to bother myself going to Linux.

Win 2k or XP Pro or Windows Server 2003 is what you want. Those are the only three windows that support SMP.

Shelnutt2 said:

Win 2k or XP Pro or Windows Server 2003 is what you want. Those are the only three windows that support SMP.

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You forgot the Original that started it all WinNT but he wouldn't want that because it lacks important features such as USB support.

Forgot about that one. (Actually I wasn't sure it it supported SMP or not).

W2k pro = 2 CPUs
WXP pro = 2 CPUs (and two logical)
WXP 64bit Pro = 4 CPUs

So if you don't want to go with a server Windows, the 64bit XP is your best (only?) choice for quad. The 64bit will also probably get a nice performance boost once the software you are using is optimised for 64 bit CPUs.

Low dual performance

Thanks a lot friends,

Are you sure Quads are not supported on XP pro? what about Linux, because there is a possibility that one of my softwares SMP version is only available on Linux(i'm using a non SMP version on win xp).

Actually i'm goin to get quad rig,
but yesterday i got my hands on a dual P3 1000 rig, i ran my job in 2 modes
dual mode gave me the results in 4 mins and 15 secs, where single mode gave it in 6 mins.

I guess low dual performance has to do somethin with mobo design (an old design of Gigabyte for P3) and it's not about the software or O.S. (XP pro SP1)
Is it true? what do you think?

By the way i've decided to go for a Quad opteron Tyan server.
Do you have any idea about it?

XP Pro 32 bit won't work with quad processors and neither will the other build on NT5.0
Windows 2003 and XP 64 bit are both NT5.1 and will support quad processors. (2003 goes beyond that in some versions and "Web server" edition 2003 will only do dual)

Linux based on a non-ancient core will support more than you will ever get your hands on afaik.

There could be several reasons why the dual P3 didn't give you 200% performance and I think the low memorybandwith could be the main one. A dual P3 system shares in most cases a single PC133 SD-RAM bus that gives you about one GB/s bandwith shared between the processors and with high latency compared to todays DDR latency.
A dual opteron system with dualchannel DDR3200 CL2 and NUMA (each processor has its memorychannel and they can access each others memory through hypertransport links) give low latency memoryaccess and theoreticaly almost 13 GB/s bandwith.

Tyan makes rock solid serverboards but aren't very overclocking friendly, but I don't think there are too many quad boards to choose from so thats probably not your main consern.

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This is what I think you should do:
Quad systems comes with a premium price over duals, one sometimes twice as high as the dual.
A quad opteron would cost me:
Tyan Thunder K8QS Pro S4882 $2000
AMD Opteron 852 $1200
AMD Opteron 852 $1200
AMD Opteron 852 $1200
AMD Opteron 852 $1200
Amost $7000 for just motherboard and processors, and you will need a SSB MED tower.

But if you instead bought :
Iwill DK8EW Socket 940, nForce4 Pro 2200, E-ATX $600
AMD Opteron 280 dualcore, 2400MHz, Italy, Socket 940 $1100
AMD Opteron 280 dualcore, 2400MHz, Italy, Socket 940 $1100
You will get the same processing power for under $3000.

(These are norwegian prices roughly converted to dollars, so your local price may vary, probably 10-20% cheaper if you live in USA)

EDIT: I hope you know that opteron 2xx processors will only do up to dual, so if you want quad you need to buy 8xx processors that goes up to eightway.

JohnDoemakt said:

XP Pro 32 bit won't work with quad processors ...

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While this is true, XP Pro can handle 4 cpus. There are no quad-core processors out yet, but they support dual core. I have a dual dual core, ala quad CPU system running XP Pro SP 0 right now.

When I write "CPU" i mean like 90% of all software companies and their licenses mean : 1 socket = 1 CPU

The number of cores does not matter.

Thanks, good suggestion, but......

Thanks , it's a good suggestion
But do you think AMD's Dual core will perform like a dual CPU?
if so , then a Quad opteron will perform like an 8 processor rig

Let me tell you this,
I ran my job on a Dual Core (HT) P4(LGA) 3.2 GHZ 800 MHz Bus and Dual Channel DDR 400, Suprisingly the software accepted 2 CPUs for calcs but Computing performance was decreased down by the ratio of 10% !!!

actualy my software is not optimized for HT so i think i wont get a Quad rig's performance of a (DUAL DUAL OPT 2xx) rig. may be i'm wrong , cause i'm not familiar with AMD's dual cores, may be they work better than intel.Correct me if im wrong.

Your suggestion really made me confused to decide what rig to Build.
Any one who can explain me ?
thanks

JohnDoemakt said:

XP Pro 32 bit won't work with quad processors and neither will the other build on NT5.0
Windows 2003 and XP 64 bit are both NT5.1 and will support quad processors. (2003 goes beyond that in some versions and "Web server" edition 2003 will only do dual)

Click to expand...

Just to be pedantic Win2k is 5.0, 32-bit XP is 5.1, 64-bit XP and Server 2003 are 5.2, and Longhorn is 6.0 (for all editions).

^^ NT5.0 will actually support up to 4 CPUs with W2K DataCenter edition I think It also takes up to 16gigs of RAM. But that's a crazy beast of an OS.