thinking of adding to the farm ..

I am looking at an HP X4000 dual 2ghz xeon with HT machine that seems a good price but i am wondering about memory on it ... and whether it would be better than a P4 HT 800 fsb system for folding throughput ...
... if i add memory will i get more than 2 folding instances running 1 big and 1 advmethods? (ChasR and Affecionado I recall reading indicate not effectively?)
.... it has 2x128mb pc800 RDRAM ... not sure i want to buy more of this to get to 512 or 1 gb since i can't use it in any other machine and not sure how much it would cost.
Looking at the specs for the tyan s2603 it says it only has a 400 fsb ....
And assuming the HP bios won't let me overclock the 2.0 xeons ....

... so i am guessing that a p4 ht 800 FSB around 3mhz with a gig of memory would be a better folding performer? (I have bought a few used mobos/p4/memory combos that would come in around the same price not including the extra RDRAM I think I would need and i have a few spare parts around to complete the P4 system for folding).

Any opinions appreciated.

Thanks

increase it to 1-2gbs of RAM... i'd say 2gb if the board can handle it, and QMD 1 CPU, and on the other CPU, put 1 BP, and 1 normal unit, and you'll get many more PPD than you would with 1 P4... heck... 4 BP instances would get ya more PPD.

Thanks Frank. But I am factoring $ into the equation ... and from what i could see new/used, I could probably build a second P4 system for what the extra memory would cost to bring it up to 1 GB - the HP system unit only has 256 MB.

i know. RDRAM is expensive. What you could do is instead build 2 cheapy p4's... with 768MBS of ram each.... and put QMD's on each of them, for very likely less money that you would likely spend on the dually xeon

value of 2xP4's vs 1 daul xeon

I think i can get the dual xeon with 1GB ram for a bit under $500 Cdn while I expect it would be at least $600 Cdn for 2 P4 HT's with 1GB ea.

Opinion on which would be a better on in terms of $ per PPD?

I also have to consider 'the containment factor on my growing farm with my wife and a single box will be easier to house(and fund) from a domestic perspective ... i know I am a folding addict but I haven't quite got the rest of the family hooked (yet).

i'd go with 2 boxen.

more PPD, and you can always set one up as an entertainment center for movies, music, etc, or as a file server.

Two P4s will put out almost twice the PPD of a Xeon duallie running QMDs because of the memory controller bandwidth limits.

However if you plan on using that Xeon duallie for other stuff too like video encoding or 3D rendering then you would want a duallie rather than a single processor sytem.

Thanks for all the advice Frank and Audioaficionado (and sorry about not getting you nick right in an earlier post -must be a sign of old age)!

So a cpl more questions ... since i don't know when a good local mobo/p4 ht combo will come along, let alone 2 of them (US sources for used are not cheap in Canada after shipping and duty) .. I am still considering getting the dually possibly followed by a good p4 when a good one comes along.

What concerns me the most about the dually is its 400 fsb. From a pure mhz point of view i would guess that with 2x 2ghz ht xeons are going to be 33% faster than a p4 ht at around 3 ghz. But QMD thoughtput (and to a lesser extent big and normal WU's?) will be hampered by the memory bandwidth.

So how much more, if anything, would it be worth to pay for the dually than a P4? Is is worth paying a bit more for the dually described in my first post than a single P4 at 533 or 800 fsb and around 3-3.3 GHZ (my assumed stock or possibly overclocked cpu speed) assuming each machine will have 1GB?

A second question - is there a link or some advice to a guide to benchmarking folding?
When i get some more time to play with overclocking/tuning my rigs, I would like to base my tuning on folding rather that artificial benchmarks. Any normal workload i put on my machines is not an issue so I want to optimize for folding.

Thanks again for your excellent help through not only directly through this thread, but also through all your other contributions I have read!

with a dually xeon, go with just 4 BP's

I used to have a dually xeon doin' that, and it put out about 500ppd or so average.

I get ~550PPD on my 3.3GHz dual Xeons and ~475PPD on my one 3GHz P4.

You can probably build two P4 rigs for a little more than one Xeon duallie and get almost twice the PPD.

If it's just a dedicated folding rig. then stick with P4s. If you wand to do some heavy multitasking, then get a Xeon duallie.

Thanks AudioA! You have confirmed the conclusion I have slowly been arriving at ... and with the dually i was considering relativly slow that really cements the issue for me. Nice setup you have!