10 BENQ 1640's in one machine - strange happenings



We have 10 BENQ 1640’s in one Coolermaster Stacker case. We have 8 drives powered up, and when I burn to 8 of them at once with Nero, during the LEADIN and LEADOUT write the machine restarts (no dump).

Specs are:
Antec 430W
4 Drives on Motherboard
6 Drives on SIIG IDE Cards

I would think this may be a power issue since the computer just restarts with no error. I did however get an Error Code one time after the restart.

Any ideas of what would be causing this? I’m going to get a 500W power supply but I don’t think that is the issue.



In my opinion, a 430W is not sufficient for all these drives. If I’m not wrong, Cooler Master’s Stacker case have a connector to connect 2 PSU together to the same mainboard. Try to use 2 PSU in this way.


Would a single 500w be sufficient? I know the Stacker has a space for 2 power supplies, just not sure how the two work. I guess I could but the MB + HD + 3 DVD Drives and then the rest on the second?


I think you NEED a second PSU, that’s a LOT of drives, each one probably drawing 1.5a, that’s 15a @ 12v!!! No wonder it restarts!!! I think a second PSU would be in order, use the 430 to power everything EXCEPT some the drives, and get another PSU to power just the drives. Look for a kinda cheap PSU, one of the older single 12v rail ones that has about 20a available on the 12v rail. You could probably put 4 of the benq drives on the 430, as long as there aren’t a bunch of other drives on there. No matter what PSU you get, it probably won’t run 10 DVD burners unless it will do about 20a @ 12v. An old AT type psu would be ideal, and have it so a relay switches it on and off with the rest of the machine. I dunno, there are a lot of ways to do that, but you definetly NEED 2 PSUs. :eek: :rolleyes: :Z :Z :Z :doh:


I see DVD duplicators with 10-15 drives with only a 400w supply. Is it because they dont have a MB and hard drive?

I will see what I can find, but chances are I’m going to just put in a 500w antec PS and see what happens.


Actually, it’s because they don’t ahve a motherboard CPU and video card to supply. Modern computers ABUSE the 12v rail, the processor, sometimes the video card, and certain motherboard components all draw power from the 12v rail. Usually the processor draws between 50 and 100w on the 12v rail, that’s anywhere from 4-8 amps, and then you have hard drives which draw anywhere between .5 to 1.5a! Trust me, you need TWO powersupplies, there’s now way one will do the job unless it’s a HUGE BEAST! A 500w Antec DEFINETLY isn’t going to do the job, I had a 550w true power, and it only did 18a @ 12v I think. If you were going to TRY to have just one powersupply in there, you should do it with one that has dual 12v rails. That way you’d have one for the mobo, and the rest of the conponents, and the other for drives and stuff. My 500w fortron blue storm has dual 12v rails, both of them 15a each. That MIGHT be able to handle the load, but it’s PUSHING IT!! It would be MUCH BETTER just to get a second PSU, and take some load off the 430. That way whatever PSU you get isn’t STRESSED to the max!!! There’s a nice little guide on how to do dual PSUs in here, it’s even a sticky. One PSU isn’t going to be happy with 10 drives!!! :rolleyes:


Well I have the CM stacker case with 8 opticals (see sig) and 3 hard drives. I am using two 350W PSU’s. One antec, one cheapo brand. I definatly agree you need 2 PSU’s. I am also powering a water cooler, lights, fans. Also all my PCI slots are filled with hardware. I rarely use more than 3-4 burners at once, but using 8 at once is a lot of power draw. Definatly reccomend 2 500Watt PSU’s


you could get a 700W Zippy PSU with 45amps on a single 12v rail and be fine…but it’ll run ya a cool $310 from newegg :wink:


Stacker case have a special connector to bridge two PSU on the same mainboard. I see is on the specifications on cooler master’s web page. I think that the best solution is to use two 400 or 500W PSU.


Where do you get those figures from? If you read the specs of harddrives, they are more like 5V@300mA and 12V@500mA. mA is milliAmps, which is 1000th of 1 Amp, so 500mA is 0.5A. I think the figures are more like for rewriters. My LiteOn says 1.5A for both voltages.

grundyv2, here’s some formulas for u:-
power consumption:
watts=current * voltage, where current is in amps (not milli-amps)
convert mA to A:

So for your 10 Benqs asumming they use 1.5A@12V & 5V, this will be:
1.512 + 1.55 = 25.5W
25.5*10 = 255W
This is only the drives, which excludes every thing else!

As for PSU watt rating, I wonder if it applies to total watt or total for each power rail. If, for each then you only need to calculate for the higher consumption only, i.e 12V.


This site allows you to check your needs:


Give yourself 15% margine or you will wear out your supply much faster. You are way past your 430 watts.


I was figuring 12v draw only, most PSUs have more than enough juice on the 5v rail, because hardly anything really draws off of it anymore. Like I said, hard drives draw anywhere from .5a to 1.5a on the 12v rail, I have a bunch of hard drives here that I can give the specs on. The fuji 10,000 RPM SCSI hard drives I have here draw 1.5a each @ 12v. The 12v rail is the one to be concerned with, because that’s the one that is taking the most abuse. Your calculations are right for wattage draw of the drives if they draw 1.5a on both rails, but somehow I DOUBT they draw that much off the 5v rail. I would take a meter and measure it, but it’s not really worth it, and I’m too lazy. The motors in the drive all run on 12v, and the electronics don’t draw that much. I seriously doubt that they eat 1.5a @ 5v. Even if they did, the 5v rail on most powersupplies is OVERKILL anyways. Really, the important thing is to make sure that you get another PSU with a decent ammount of current on the 12v rail. The 5v rail really isn’t going to make a difference, because the second PSU is going to power JUST drives. There’s no way the drives are going to draw enough off the 5v rail to make it puke, but the 12v rail is being loaded down quite a bit. Total wattage IS NOT important, 12v rail current IS. :iagree:


Yes, you’re right. I didn’t know they draw so much more. I agree as well the 5v rail is not really used by other parts.

grundyv2, it seems PSU are quite a bit - it’s quite a percentage of getting another system. It’s just an idea, how’s about gettting another PC (maybe lower spec) to manage some of the Benq’s.


I would def double up on PSU’s, especially if your case provides a feature to stack two of them. Get two 500’s or two 550’s from Antec and save youself a headache for years to come.


Wouldn’t it be a bit better if he did some research aka trial 'n error first?
Disconnect like 8 drives and see if still happens for instance.
Might aswell be the SIIG cards, SiImage chips aren’t exactly known for being great.


Yes my benq 1625 didn’t like being on the SIIG card. Moved to my motherboard and it ran perfectly.