replying to Roger Mills, tahrey wrote: If you've got four years use out of each battery, you've done extremely well. I've not known laptop lithium batteries to last longer than that. Three years is more par for the course, and their usable capacity is already on the slide by the end of the second. The laptop I'm typing on is entering its sixth year, and has its second battery in place, which is already down to about 20% of original capacity. As the system is set to shut down into hibernation at 15% (a seemingly vain attempt to prevent over-discharge and the lifespan reduction that causes), that essentially means the machine is completely tied to the mains and the battery is only really useful to keep it alive for a couple of minutes when moving it between rooms (or sockets in the same room) without shutting down, or as a safety "parachute" if there's a sudden power cut.
That doesn't mean the power supply is behaving itself however - I've had to get an HP-Compaq laptop PSU replaced before as it failed in such a way that it had just enough power to run the laptop in light usage conditions, or charge the battery in a slightly sluggish fashion when the machine was turned off, but not both at the same time (and high power use would gradually drain a full battery). Whilst the battery is almost certainly dead, its death might have been hastened by a dicky supply. Sadly the only way you can really test it is by installing a working battery and observing the power-on charging behaviour, maybe with a third party battery / power use monitor utility (or an OEM one if they bothered to supply such). With the battery fully drained, it should be able to charge at a rate representing 0 to 100% in under two hours (or just one hour for some models), which then tapers off above 80~85%, with the machine turned on but idling or only working lightly. With the processor, graphics and disk working hard, that rate shouldn't drop to less than half and there should still be a taper-down noticeable above maybe 90%. Alternatively you can plug it into a power meter and see how much the PSU draws. At full tilt it should be somewhere around the rating printed on the body; if it's significantly less (below 75% or so, and particularly under 50%) even with the cooling fan howling and your lap being thoroughly cooked then it's probably defective.
An eight year old laptop, though, that's very much prime for replacement. I keep my computers running as long as reasonably possible, and then a little more, and I've not yet managed to keep a machine operating in a satisfactory manner with contemporary software much beyond its 7th year. At least not for those of middling to slightly above average performance, which tend to be the best value (not "cheapest"). If it was originally a top-of-the-range model I guess you may get an extra couple of years (I've seen Core 2 Duo/Quad desktops stretch well into their 8th year whilst still being just about usable), but even then I'd suggest you'd be better off resigning to the idea that it's had its day, and the failed battery and potentially iffy power supply are good reasons to replace the entire machine. You've definitely had your money's worth out of it, and even the cheapest, nastiest machine you can buy now will significantly outstrip a high end machine of 8 years ago in terms of performance. I'd be looking to replace this one already (the generational shift to 64-bit operating systems is increasingly leaving me disappointed when looking at the minimum specs of otherwise attractive software, as it only has
32-bit Windows and there's no point spending money on an OS upgrade for a machine that may only have another 12~18 months of service left in it), if only I wasn't out of work and increasingly short of cash right now.