Brian said:
I've got a PC that I built two years ago (from arstechnica.com's
Budget Box guide). I put a SATA drive in it, and it continually had
problems with drive corruption, so I recently put a new SATA drive
into it, which is also now having corruption issues. People keep
telling me I need a better power supply.
How many amps does a Serial ATA hard drive need?
My system is a Athlon A64 3000+ on a Socket 939 board with a PCI-E
GeForce 6600 256MB with 1.5GB RAM. It's got a DVD-RW drive which I
hardly ever use, my SATA 160GB drive, and an ATA 60GB drive for
backups. Rounding out the lineup are a floppy drive, a serial keyboard
and serial mouse, and a USB earphone/microphone.
Powering it right now is an A-Power 500W unit which provides 17A on
the +12V rail. Is this not enough? What amperage do I need?
The worst 3000+ there is, tops out at 89W. 89W/12V * (1/0.90) = 8.24 amps
at 90% Vcore conversion efficiency. You can look up your actual numbers,
on
www.amdcompare.com , based on the OPN order number of the processor.
A 6600 video card, draws 12V @ 4A from the slot. Just a rough guess.
(I could look it up, but that won't be far off.)
Hard drives idle in the desktop at 12V @ 0.6A. There is some power from
the 5V rail, like 5V @ 1A, but we're working out the 12V draw right now.
The DVD won't draw appreciable current from 12V, until media is inserted
and starts to spin. I've measured my CD drive, and it draws 12V @ 1A when
the media spins at top speed. The boiler plate spec on CD drives is around
1.5A, and the more exotic opticals draw even more than that.
I allocate 12V @ 0.5A for fans, but you can check the label on those.
So, if you were playing a game with no DVD in the drive, the current on
the 12V rail would be:
8.24 + 4 + 0.6 + 0.6 + (0.0) + 0.5 = 13.94 amps
Your A-Power is just big enough (I like about 3 amps margin). If there is
a DVD in the drive at the same time, you're still OK.
A 500W rating is meaningless, unless the amps are put in the right place. If
you are offered 5V @ 40A, and the machine uses only 5A of the 40A total,
the power supply is poorly proportioned for the application. Modern
machine draw most of their power from the 12V rail, so excessive capacity
on the 3.3V and 5V rails doesn't help.
Now, tell me something. Does the ATA corrupt ? Doesn't it bother you,
that the SATA corrupts and the ATA doesn't ? Do some extended tests with
the ATA, and see if you can get any errors on it at all.
I'd say, like all problems, eliminate the potential causes one at a time.
Buy a decent power supply. For example, the power on this one, is an
unimpressive 470W, but notice how all the major rails are beefy.
It means any one individual rail can be heavily loaded, and still work well.
The sum total of all power consumptions, still cannot exceed 470W. Your machine
will not go over about 250W worst case. So total power is not the issue.
But current limitations on one rail *might* be.
+3.3V@28A,+5V@32A,+12V@26A,
[email protected],
[email protected] 470W total $75
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703011
Other things to play with:
1) Is the SATA cable in good shape ? You're not supposed to kink it.
Neither would I recommend tightly wrapping restraints around it.
2) You don't say what chipset the motherboard uses, but there have
been complaints about disk corruption with some Nvidia chipsets.
I've never seen any followup or resolution on those complaints -
like whether the individuals affected just threw away the boards
or what happened to them. Based on that, I'd Google the hell out
of your motherboard model number, chipset names/numbers, the
word "corruption" "disk" etc. If there is an issue, you'll find it.
I believe the corruption even has a characteristic pattern to it,
so when doing your bench testing, you may want to keep an eye out
for whether short strings of contiguous bytes are what is being
corrupted. That means doing file comparisons some how.
HTH,
Paul
