Laptop AC adapter - 90W vs. 70W

Factual Questions
1

Unfortunately for my friends, I’m kind of the “computer guy” amongst us. I know more than them, which is not a lot and puts me into the “just enough knowledge to be dangerous” category.

Anyway, the latest project is a dead laptop.

HP ze4500
Running XP
Had 1G of RAM

This laptop was brought to me dead.

I fire it up and no OS is found. After many trials and tribulations I install XP with the restore disks, in the process discovering that one stick of RAM is bad (so now we’re on 512MB).

The AC adapter has long since been lost and it’s being powered (sans battery) with an aftermarket (70W) AC adapter. The OEM adapter was 90W.

The laptop will run fine with the adapter, however, any attempt to install the battery (while off) to try and charge, fails.

Could this be an issue with the power adapter being used (70W vs 90W)?

Please feel free to yell at me if I’ve left off details…

2

Can you clarify this? What exactly do you mean by “fails?”

3

I read the fine print on a 70W adapter and it claimed that it would charge the battery of one calling for a 90W, but I could never get it to work.

I had to go back to Dell and order their adapter.

As to the OP: 90W vs 70W? Don’t be silly. 90 Wt ALWAYS wins. There Can Be Only One.

4

Ah yeah… that wasn’t very clear at all.

After I replaced the battery into the bay, I turned on the computer and it began to boot and then shut down before windows even started.

That was actually last night, and I left the battery in all night and then (after I posted the thread), started the computer this morning with no problems, however, the battery shows that it is still at 0% charge, and even my computer (same age) will charge it’s battery so that it’s good for a solid 20 minutes.

So I now have a functional laptop that will not charge the battery at all. I’m hesitant to simply buy a new battery for the laptop without a good probability that it will actually charge the battery (or will I need to get an AC power source as well as a battery. At that point they’d be 200.00 in… which is about the cut-off point at which it’s better to just get a new one.)

5

Do you have any way of testing to see if current is getting to the battery to charge it? It could be something internal completely unrelated to the components you’re looking at.

6

A permanently dead battery would do what you said. It doesn’t mean that something else isn’t preventing charging. Had you the correct adapter and the computer died starting up with the battery in it, I would say it is a bad battery.

Trying to charge a battery while running a computer may very well be beyond the capacity of the undersized charger. Using a under rated power adapter can result in it overheating and starting on fire. You need to use a voltmeter to check that power is making it to the battery contacts of the case.

By the way, did you check to see if the battery is a recall yet? You may have have a free one coming.

7

Not really. I think that would be beyond my knowledge.

It could just be that the battery is completely toast then. I did check the recall status, it’s not one.

I’ll just take it back to her and let her know I’ve taken it to my limit, anything further would require someone with knowledge.

Thanks everyone!