Odd question but I'm a little stumped as to where to take this one, and was hoping to get some second opinions. I've got a mid 2007 Macbook Pro (A1226) that POSTs fine, boots fine, but only when the battery has a decent charge; REGARDLESS if the charger is hooked in or not. The battery itself still works, only barely though. I can get about an hour out of a full charge (health is around 40%) but I'm not in a situation where I can purchase a replacement quite yet. After I haven't used it for a day or two, the battery will typically be dead. I plug it in with a known good charger, but it won't power on with the power button. I have to wait about 20-30 minutes with the charger in before IT POWERS ON BY ITSELF. Charging/usage is normal after this, and I can even shut it off and power it back on with the power button as usual, as long as it has a charge. This also applies to sleep, too. If it's asleep with a weak battery, when I plug it in and try to wake it up it will not wake until it's been plugged in for at least 5-10 minutes. Again, charging/usage is normal afterwards. Resetting SMC didn't seem to correct the issue. I can charge, power on, remove the battery and turn it on/off with the charger alone no problem. If the charger is removed and replaced without the battery it won't power on again, but if I replace the battery (charged) while plugged in it powers on (with no button press). So maybe it's not the main battery. The problem is independent of the OS - this is strictly a hardware issue. Was there ever a PRAM/CMOS battery in this model, and could that be causing my trouble? It is a nearly 5 year old laptop at this point. I've opened it up a few times for HDD swaps but never noticed such a battery while working. I don't believe it's the motherboard because after having a charge and powering on, it functions fine but weirder things have happened so I could be wrong. I still have some more troubleshooting I can do on it, but does anyone have any insight?