My Acer Aspire 5612z, Dual-core celeron, 2GB ram, vista home premium 32bit, has two separate problems. Screen is filled with vertical red blue and white vertical stripes, if I tap the screen frame then the picture is ok for 30 mins or so, then goes stripey again. (Poss fault on FL board?).
Second, Laptop boots, 20 seconds, to Acer screen then stops.
Can only switch off power from that point.

Tapping the screen you could have a loose connection from the LCD Panel to the MOBO connector, but you see if you did the screen would dim out. In your case you have the the same issues that tell me that the LCD Panel is faulty. If this unit is still under warranty then have ACER service the unit or take it to ACER dealer who can either send it back to ACER or they can order the panel and replace it for you at no cost, but then it has to be under warranty. If not you'll have to pay the cost of ordering the part, labor to install it. Find out cost prior to signing any agreement.

On your other issue, did you replace or upgrade the battery or memory? If not then remove the battery and plugin the power only. Try this again does it boot the ACER logo and Windows. Can you put your ear down to the keys or palm rest and hear the HDD spinning up?
If not either the HDD is DOA or faulty power module on the MOBO or just bad MOBO. Again same as above if it's under warranty call or take it to ACER factory service dealer.

Make sure if you had a good battery on this laptop that all switches are switched to the lock mode for the battery.

i have the same model acer and the same problems. a lot of things pointed to lcd problems. i first used an external monitor to make sure the laptop was putting out video and the external worked. (hit function + F5 to toggle between lcd and external monitor). i then fiddled with the video cable after looking at the service manual to take apart the laptop correctly. i found wiggling the cable regained picture so i oredered a new cable and installed but no video. i then fiddled with the cable where it hits the motherboard and viola...video. this connection is very finicky though. i found that pushing the video cable into the motherboard slot with a lot of pressure worked the best and then i duct taped it. ive been having flickering still though. i think the problem is our motherboards suck. if you are still under warranty i would highly consider acting on it.
anywho...i think the boot problem we have is probably related to our video problem bc of our suspect mobos. here are some steps i took to help the boot problem. i first went into the bios set up (F2 at start up) and then went all the way to the right and down to restore default settings. That by itself helped the boot problem. for safe measure i also flashed the bios through acer.com. just go there then to drivers then to your model then to BIOS then unzip the file and then run the bios through windows utility. BE CAREFUL.
let me know if this helps or if you find anything new

ps
after some more research ive found that cleaning out the system fan has helped people. remove the 4 screws underneath that hold the cover in. then take the cover off and remove the 3 screws holding the fan in. i had a layer of hair and dust between the fan vent and the heatsink. havent had a flicker since. this makes sense as the problem occurs when the computer starts working hard. hope this helps with your acer 7520-5757

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