BIOS trouble!

Puffi · Post by **Puffi** » Mon Jan 19, 2009 7:20 am

I have a pickle for you all...

I have three hard drives. When I turn on the computer none of them are recognized by BIOS. I restart, and then sometimes they all are, or some of them are. So I keep restarting until I get them all to work. I changed the SATA cables, power cables, order of the HDD's... Dusted the motherboard... and that's about all I can think of.

Once the BIOS finds the drives everything works just fine. Now I'm at the point that I don't want to turn the computer off anymore just to avoid this hassle.

Everything worked fine for almost a year before this, and I haven't made any changes to anything. Speedfan says all drives are fine... So I'm thinking it must be the motherboard? Or perhaps the PSU? How can I know? What can I do?

My motherboard's the GA-P35-DS3R, PSU is Corsair 620W.

maf718 · Post by **maf718** » Mon Jan 19, 2009 3:55 pm

I had a similar problem caused by a failing PSU. When starting from cold the PC would never recognise the drives but after several attempts it warmed up enough to boot. I was tearing my hair out for ages before I measured the voltage on the +5V line, it was only 4.3V from cold and eventually 4.7V when warmed up, which was enough to start the hard drives I guess.

Normally Corsair PSU's are good quality, but if you have access to a multimeter I would test the voltages to rule it out (or in).
Edit: and if you don't have a multimeter you can probably check the voltage on the +5V rail from the BIOS.

Hope that is some help.

Puffi · Post by **Puffi** » Tue Jan 20, 2009 6:02 am

Funnily enough, BIOS shows all the other rails but the 5V... Well I checked it on Speedfan and it looked OK, but I don't know accurate that is. Speedfan shows +4.92 and +5.19V. But this is obviously after a successful boot, maybe the values are different when it can't find the drives? But ironically... Then I can't check them.

So any idea how to get the real values? I don't have a multimeter. Maybe I could cannibalize another computer's PSU and test that, but that'll take some time.

jhhoffma · Post by **jhhoffma** » Tue Jan 20, 2009 7:04 am

Go get a cheap multimeter, it will be loads more reliable than a mobo reading. You can find them at the local hardware store. Usually budget models start around $10.

Puffi · Post by **Puffi** » Tue Jan 20, 2009 11:51 am

Hmm. Maybe I can get a multimeter then. So how do you measure it? Just pick the HDD's power cables and stick the (whatever the measuring things are called) in the holes and turn the puter on? Should I disconnect the other cables, or do any other preparation for this?

andyb · Post by **andyb** » Tue Jan 20, 2009 4:08 pm

Hmm. Maybe I can get a multimeter then. So how do you measure it? Just pick the HDD's power cables and stick the (whatever the measuring things are called) in the holes and turn the puter on? Should I disconnect the other cables, or do any other preparation for this?

Test a Molex connector instead, it will be a nightmare to test a SATA power connector, and the voltages will be the same. Red and either black BTW, the yellow is 12v FYI.

Andy

Puffi · Post by **Puffi** » Fri Jan 23, 2009 2:14 am

OK I got a multimeter and measured the rails... Or at least I thought I did. Set to DCV 20 the value climbs up to 900 on the 5V. The 12V showed something over 2000. So there's thousands of volts going thru this thing?

I suspect I'm doing something wrong...

Also when I got the multimeter 1 of my HDD's totally failed. I've restarted the computer like 20 times and it doesn't find it anymore, BUT the other 2 HDD's are found instantly now! The 1 that failed is (of course) my 300GB WD Velociraptor, so it's a bit different from the other 500gb storage drives.

Is it possible that one failing HDD can somehow prevent other HDDs from showing up on BIOS?

Puffi · Post by **Puffi** » Fri Jan 23, 2009 12:27 pm

Ehm... I decided to change the multimeter's battery

I got 5.02V on the 5V rails. I'll RMA the Velociraptor. But my last question still stands:

Is it possible that one failing HDD can somehow prevent other HDDs from showing up on BIOS?

It SEEMED like when the Velociraptor was still limping it was bringing the other HDDs down with it, but once it completely failed the other drives were free to work normally.

...Or was/is this problem something deeper on the motherboard?

maf718 · Post by **maf718** » Fri Jan 23, 2009 5:21 pm

At least you know it's not the PSU now.

Normally I would say if you remove a component and your problem goes away then you have isolated the problem. I guess you just need to monitor the situation with your remaining drives while waiting for RMA confirmation on the velociraptor.

sjoukew · Post by **sjoukew** » Sat Jan 24, 2009 5:20 am

Puffi wrote:Ehm... I decided to change the multimeter's battery I got 5.02V on the 5V rails. I'll RMA the Velociraptor. But my last question still stands:

Is it possible that one failing HDD can somehow prevent other HDDs from showing up on BIOS?

It SEEMED like when the Velociraptor was still limping it was bringing the other HDDs down with it, but once it completely failed the other drives were free to work normally.

...Or was/is this problem something deeper on the motherboard?

If you have all harddisks connected to 1 hdd controller, yes it can. If your velociraptor is issuing certain commands to the controller in such a way it gets stuck or crashes, the other drives are also invisible, because the controller isn't working anymore.

I have seen this before.

Puffi · Post by **Puffi** » Sat Jan 24, 2009 8:05 am

I have seen this before.

That's good to know. I've had a bunch of HDDs fail on me before but it never affected the other drives. I don't have any extra controllers or anything so I guess that's it then. Everything works just fine now on the other drives. So fine in fact that I'm beginning to question the decision of paying 260 euros for the Velociraptor in the first place...