Hello,

Been speccing up a new dual opty 250 rig for digital audio processing, but I need some help with the PSU.

basic setup is...

2x opteron 250s
Tyan S2895 nf4 motherboard (not out yet Smile
4gig (4x1gig) ddr400 corsair ecc registered ram
4x 76 gig sata WD raptors
nvidia quadro nvs pci-e graphics card
coolermaster cm stacker case
misc extra fans and gubbings for cooling
several pci audio cards

Ive actually already purchased most of this kit, im just waiting on the motherboard to be released now.

Stupidly I went ahead and bought a psu without doing any research (all puters use the same psu, even dual setups I thought....not)

I purchased this little fella for £70

http://www.thermaltake.com/pur...049a...w0049atx12v.htm' ">http://www.thermaltake.com/pur...atx12v/w0049atx12v.htm

Thinking 680w will be enough for anyone. But after reading more forums and web sites Im now worried if this was the right choice and will it work at all?

It has eps 12v support, and the 24pin/8pin connections to go into the tyan fine, and 680w should be enough to drive my setup I think. But the v12 rail output is whats getting me.

I read this lot on a website....

"There are two types of 12V rail configurations for systems: 'Common plane' and "Split plane' processor power delivery. The 'commob plane' system has both processors powered from a single 12V rail (+12V1) from the power supply. The 'split plane' system has both processors powered by seperate 12V rails (+12V1 and +12V2) one dedicated to each processor. The system in both cases, has an additional 12V rail to power the rest of the baseboard +12V loads and dc/dc converters. +12V1, +12V2 and +12V3 should not be connected together on the baseboard to ensure that 240VA protection circuits in the power supply operate properly

Table 6: 12V Rail Summary
........................................................................................................................................................................................
Common Plane System........................................................Split Plane System
+12V1........Processors.........................................................+12V1........Processor 1
+12V2........Baseboard components other than processors.......+12V2........Processor 2
+12V3........Drives and peripherals..........................................+12V3........Baseboards and components other than processors
...........................................................................................+12V4........Drives and peripherals"


So I'am guessing my psu is the common plane version as it only has 12v1, 12v2 and 12v3 rails, and this means both opterons will be using 12v1?

I dont really have a clue about wattage, amps and volts, but I think the opty uses about 90watts of power which should mean about 8 amps per 250 cpu?

This psu only supports 15amps on the 12V1, so if my calculations are correct this psu may not be powerfull enough to support my cpus (please correct my calculations if they are wrong, I dont really know Smile

Even though ive come to that conclusion which may be totally incorrect, I have read on many websites people with even more powerful setups using lower rated psus and even less on the 12V1.....so im really bloody stuck here and basically just want to know if this PSU will run a moderately to high specced dual opteron 250 workstation or if im getting all worried about nothing and have more that enough power?

Thanks for any insight or help.

ten

-------------------------
- Project TEN
- SuperMicro H8DCE nf4pro - 4x1GB Kingston HyperX ddr400/3200 er @ 2.5-3-3-6-1-numa
- 2x DualCore Opteron 275s - Thermalright XP90c - Thermaltake 92mm Silentcats
- 4x Raptor 73GB 10K sata drives (2x raid 0) - 2x Maxtor 300GB +10 sata drives<

While split rails probably can work better(if designed properly) , I don't think you will have any problem with the PSU you selected as it has the correct extra power headers for your board, and I think it has ample power for your dual 250's and probably a 6800 ultra as well.

And it is decent brand which should have quality components...so don't worry be happy