WWYD?

lazyart

Just thought I'd lob this one out to techs and budding techs alike.

I get a computer today. No video, no beeps on power up. CD-ROM does power up and power supply fan is functioning. Owner says it just started doing this. I connected my known good devices- motherboard, keyboard and mouse- and got the same result.

Oh, and to complicate matters, its a HP (if you've never worked on a proprietary PC, understand that they are usually hell).

I'll be back in a bit with the rest of the story. I'm just curious what others would have done.

RussS

First off - replace the power supply. The fan can work without sending power to any other part of the system.
I have in fact seen power spiked machines that the only thing that worked was the PS fan and every part of the machine was toasted.

bellboy

my sister had a pc like that.

check to see if the speak is connected too. you may have no sound, but it might "want" to beep

i have seen computers that will fail to boot and fail to beep when vga, ram or keyboard are not connected or faulty.

lazyart

Well, it turns out I couldn't swap the PS-- I didnt have anything of the sort (proprietary absolutely sucks).

I searched around the place here but couldn't come up with a PCI video card. So much for my first guess.

So, I then started up the machine with my hand on the base of the heatsink. The fan is spinning but the HS didnt even get warm, so I figured the CPU isn't fried (they get extremely HOT when that happens).

Looking into this cramped space I figured the only other option is to pop out the RAM and move it to the other slot. After 10 minutes of struggling I was finally able to do this (oh god i hate these cramped cases).

Beep. Beep Beep Beep. Beep Beep Beep. Beep.

Well, at least it's something. HP online says either the RAM or the motheboard is suspect. Well, I didnt get anything in the first slot, but beeps in the second. DIMM slot 1 is bad? I remove the stick, put in a known good stick in slot 2. Same result. I'm convinced the board is bad. I start looking up prices on a replacement motherboard (generic, of course) with a new case and floppy drive.

I walked away from the machine, but something just didnt seem right. Some motherboards are picky and just won't boot without memory in the first slot.

So, I take my known good stick and put it in slot 1.

...IT....IS.....ALIVE!

Great, it just need a new stick of memory!

But that didnt sound right either. The suspect stick did the same thing as the good sticks in slot 2.

So, once and for all, I put the original stick back in slot 1.

It boots.

So it seems the original stick just needed to be reseated. Unfortunately because of the cramped quarters that wasn't obvious. Owner later tells me that the machine had never been opened before.

Never saw that before. I didnt think DIMMs would do that. Oh well. Just a bit more bench experience for me.

cheeblie

Heat can do that over time. It's called chip creeping, but I've never actually experienced it. I guess you're one of the lucky ones to experience such a great phenomenon :P .

lazyart

I've heard of chip creep, but i thought it only applied to SIPP memory (from waaaay back in the day). The latching mechanisms of SIMMs, DIMMs and the like is supposed to prevent that.

RussS

True enough - however I have seen many a SDRAM module on new machines that only have 1 clip correctly seated - that usually leads to creep eventually.

VTEK

Lazyart:

I had the same problem with an HP as well. Tried all the same things, I was the second tech on this thing, may mistake was beleiving the first tech when he said he checked the RAM ( his check was , no beep can't be ram). I learned not to trust HP or the first tech....

lazyart

Considering the cramped layout (and let me say just one more time-- proprietary totally and absolutely SUCKS), this stuff really happens. There was NO WAY in the world I could get to the second clip without removing half of the components.

My hands are too big for this type of work. But I love it.

RussS

I bought a cool torch with a flexible neck and a small mirror with a swivel head from an auto parts store - awesome for looking under power supplies on mini systems

bellboy

i used to have a torch for working on systems. wonder where it went?

RussS

<< Not guilty

lazyart

I would've like to torch that system.. is that the same thing?

RussS

heh heh heh - kind of remind me of a lady who called me and said that she had a little accident with her laptop and needed a quote for the insurance company. Her claim was that she dropped it - I don't however think she told the insurance company that she dropped it from the window of a 3rd floor office .... lol