|emachines desktop computers are well known to have el-cheapo power supplies that tend to fail more often than average, and when the power supply fails completely, they are a lot more likely than average to damage something else, often the mboard.|
If you have not been fiddling inside the computer case just before this happened and have not changed the ram installed in it, it is very likely that if you replace the power supply BEFORE it fails completely, doing that will restore your system to working properly again.
Unplug the cord to the computer, or otherwise switch off the AC power to it, open up the computer case, and find the label on the power supply - if the brand is BESTEC I advise you, if you find ANY indication the power supply might be in the process of failing, DO NOT trying booting the computer anymore - if the PS fails completely there is a strong likelyhood it will trash your mboard!!!!
Failing power supplies are common and can cause your symptoms.
They often partially work, fans and hard drives may spin, leds may come on, yet you may get no video and the mboard will not boot all the way.
Check your PS.
See response 4 in this:
"Intermittent no boot emachines"
In the initial stages of the power supply failing, they often work okay intermittantly.
DO NOT replace the power supply with another BESTEC one!
In most cases you can replace it with a standard sized standard ATX power supply.
If you HAVE been fiddling inside the computer case before this happened
- remove the AC power to the case the same way, check to make sure all connections, cards, and ram are fully seated.
"It could be a heat problem."
While you're in there, if the cpu fan/heatsink has mung (dust, lint, etc.) on it, clean it off, but DO NOT use a vaccuum cleaner to do that (they produce a tremendous amount of static electricity when running, and anything connected to them can discharge that to your components) - use canned air, or an air nozzle if you have access to an air compressor, or an artist's brush that can be used in small spaces, etc. It may be difficult to clean the top of the heatsink under the cpu fan - the most likely place to have mung on it - and the bottom side of the cpu fan blades unless you remove the fan. If you have a case fan, clean that too if it needs it.
With the cover still off, restore the AC power, start the computer and make sure the cpu fan spins - if it doesn't spin, if you're sure the power supply is working okay, don't use the computer until you have replaced it.
If it spins too slowly, and/or if it makes rattling or screeching noises, most likely to be noticed when the computer has cooled to room temp, has not been used for a while, and then is started up, the cpu fan's bearings are failing - replace it as soon as you can.
If the PS is failing, you can usually replace it with any decent standard sized standard ATX PS with the same capacity or greater.
Standard (PS/2) power supply size - 86mm high, 150mm wide, 140mm deep, or 3 3/8" h x 5 7/8" w x 5 1/2" d , or very close to that, though the depth can be more or less for some PSs.
Don't buy an el-cheapo PS.
See response 3 in this:
A frequent mistake people are making these days is they have installed a video card their power supply hasn't got enough capacity to support.
Your power supply must have at least the minumum capacity required to support a system with the graphics card you are using installed, or the max graphics card you might install in the future.
(Onboard video - video built into the mboard - IS NOT A CARD!)
You can go to the video card maker's web site and look up the specs for the model - often under system requirements - the minimum PS wattage, and, more important, the minimum amperage the PS must supply at 12v is stated. If you don't find that, any card with the same video chipset including any letters after the model number has very similar minimum PS requirements.
If the power supply does not have enough capacity, the video card often works fine at first anyway, but the PS is overloaded 100% of the time the computer is running and the PS is damaged and will eventually fail completely.