I have been having some serious stability problems with a video editing PC i built at work. The problems all centre on the 2x RAID 5 arrays and the RAID controller card as we have been having frequent drop outs and array failures. All seven of the RAID drives have been replaced, the RAID card has replaced under RMA and all the SATA cables have been replaced. The failures do not seem to happen to particular drives which is why we thought the RAID card was at fault. Adaptec , the card manufacturer, suggested the PSU was not powerful enough but when specifying the PC i had contacted Corsair with the full hardware spec and they said the PSU was ok. At the moment we have the RAID card removed and 3 of the HDD's disconnected from the PSU and it has not crashed once so i am binging to wonder if it is the PSU. Full specifications of the PC are: Tyan Tempest i5000XT 2x Xeon E5320 Quad Core 2x 2Gb FB DDR EEC X1950 Pro Matrox X2 Video Editing Card Creative X-Fi Platinum Adaptec 2820SA SATA Card 1x WD Raptor 7x WD 500Gb RAID Edition HDD's 2x DVDRW 2x ICY Box SATA RAID Back Planes 1x USB Card Read Corsair HX 620w PSU I'm sure when i was specifying the PC i checked the xtreme PSU calculator which at that time came to well under 600 watts. I checked it today and it now comes to 614W normal and 637w under full load. So my main question is is there a way i can monitor the PSU to see if it is running out of power? As this is a server board a lot of the apps that measure voltage etc, such as speed fan, do not work.
You can buy a Kill-a-Watt or similar power meter to see what the system is drawing from the wall. When you're looking at that power draw, bear in mind it's AC draw, and the PSU is rated in DC draw, which is roughly 80% of AC for that power supply. If the power meter says you're pulling 775 watts or less, you're within spec for the power supply. However, I very much doubt you're using quite that much power. You've got a hungry system, no doubt, but the Extreme PSU Calc generally overestimates power requirements by quite a bit. With lower-powered desktop systems, the error can easily be 300%, and in those situations I tend to recommend this calculator. I suspect, though, that for a system this demanding, the Extreme results are closer to correct than they typically are. I think your best bet is to buy a power meter and make sure you're pulling a safe wattage.
Hmmm, those Xeons will be drawing 200+W between them, the video cards, probably will draw another 200W, leaving only 220W for the rest of your system. The RAID array or 7(!) drives will draw about 80W (~11W each when performing RW ops according to the WD website). That leaves only 140W, now, FB DIMMS are power hungry, and I'm sure the mobo will draw at least 50W, so I would say you need a bigger power supply. When you're using the system, does the PSU fan speed increase or does it stay high? Personally, I'd add up the wattage of each of your components (the data will be available on line somewhere, but may take some digging) and see what it comes to in total. Then start removing components that are very infrequently used (DVD Drives for example). Once you have a power figure, add 25% and then get a PSU with that wattage (I'd say you'll need an 750W PSU for that system). Hope that helps. Andy P.S. Note that I'm assuming that when you're video editing, the CPUs are fully loaded, the memory and graphics cards are running at nearly full power and the HDDs are getting written to constantly. (I'd love to be able to build a system for work, sadly they are in Dell's pocket and won't even consider a self built system).
This is not actually a very reliable approach to the problem, because the published wattage values for most hardware are theoretical maximums rather than actual consumption. Technically, you've already tried this approach, because I believe the Extreme PSU Calc uses the published values for components, so you have nothing to gain by painstakingly doing the research and calculations manually. Honestly, the fastest and most reliable way to find your consumption is to buy a power meter and check your AC wattage. Multiply this value by 0.8 (because your 80plus PSU is roughly 80% efficient at typical load levels) to find your DC wattage, and see if it's within the capabilities of the PSU.
Thanks for the replies and yours in particular crazybob. I have added a power meter onto my next order as its a cheap way of checking out the consumption. I'll post the results.
I'd say check the usage under load at the wall as has been suggested. I'll also mention that in an ideal world, you should be using no more than 75% of the units max load for any extended period of time.
Well i got the power meter and its definetly not the PSU. Running everything at full load it peaks around 420 watts so i have 200 watts to spare. I think i have traced the problem down to the backplane of all things. Need to do some more testing to confirm though.
