Acer Aspire 7720-6155 wont boot

It may be a problem with the hard disk drive. To check, try to boot to the BIOS. Turn the computer on and tap on F10 before the Acer splash screen. Once you are in the BIOS, check if there is any hard disk drive being detected by the computer. Look for any SATA device that will have a storage capacity. If it does not show such, then you have to replace the hard disk drive of your computer. Unfortunately, the data goes together with this device. It will be very expensive to retrieve it from a damaged hard disk.
If in case the hard drive is seen, then it is just an OS problem. The MBR is corrupted. To fix this issue you need to boot from the installation CD.
For XP: boot to the WinRC.
Tap on F12 on before the splash screen. You will have an option to boot from the CD. Load the WinXP CD and choose onboard or usb cd rom drive.
On the setup screen choose R to repair. The follow the prompts until you get a black screen.
On this black screen, type fixmbr then press on return. That should do it.
If it does not work, then you just need to have your Hard disk replaced.

Acer Aspire eRecovery
The Acer Aspire eRecovery tool comes in both a DOS and a Windows version with the Windows version offering more features. To open the DOS version, boot up your computer and press the Alt + F10 key combination when you see the Acer splash screen. To open the Windows version, allow Windows to load and then open Acer eManager followed by double-clicking the eRecovery link.
Using the eRecovery tool is fairly simple once you have it launched. You can either restore your Acer Aspire to factory settings from the hidden partition or with the recovery CDs. Once eRecovery loads, you may be prompted to enter a password. According to Acer, the default password is: 000000. If you have not changed the password, enter these six zeros when prompted.

You can try safemode by Tapping F8 when the system turns on
if the system boots into the Safemode try System Restore
1.Start menu
2. All Programs
3.Accessories
4.System tools
5. System Restore
6. Select a Date which the system worked fine
Or Else
Tap F8 try Last Know Good Configuration
if it did not help
Try re-installing the Operating system
Steps to Re-Install OS
At the Acer splash screen, you can press Alt and F10 to bring up a DOS style version of eRecovery. The unit is able to reload Windows from this mode faster then from CD. If the hard drive is replaced the system loses its eRecovery features. These features are on the hard drive and cannot be reinstalled

Does the splash screen come up? Most of the time if it is your hard drive the ACER splash screen will come up and then a Hard disk 0 error after that. If nothing appears on the screen then you have a bigger issue.

Is there any noise at all (Fan, hard drive spinning)? If so try hooking it to a external monitor to see if there is any movement. You might have a problem with your LCD.

There are numerous issues that could cause this but if absolutely nothing happens, no lights, no fans, nothing then check the power supply. Use a simple voltage tester to see if you have any voltage on the connectors going to the hard drive and cd/dvd drives. If not this is a pretty easy and relatively inexpensive fix. You can e-mail me at [email protected] for more help.

The computer can't see the hard drive for one of many reasons.
1. Hard drive failure
2. Bad connection between hard drive and motherboard.
3. BIOS corrupted
4. Motherboard failure of HDD control.

Press F2 when the ACER splash screen appears and go into BIOS set up.
The first page should show the hard drive name and ID number.
This may be missing or have corrupted characters in it.
Go along to the 'save and exit' and allow a restart. This sometimes kicks it into life.
Replace the hard drive with a known good one and check to see if this is recognised in the BIOS.
Clean the contacts of the hard drive.
ACER fitted both types of hard drive to this model, either PATA (IDE) or SATA.

More than likely a virus or a video card. Hopefully the video card because if it is a virus then you will have to replace the hard drive. Hope this helps

plz try by reinstalling the operating system, if you cant then plz check your hard drive

Hi , Boot the PC and keep pressing F . a screen pops up seletc the last known option and enter and then jst boot the system.

If you dont see any green lights and you dont hear any boot up sounds ( hd, fans, etc) try to take out battery and just plug in the AC adapter to a known good power outlet. Make sure your power plug is good too. If you hear boot-up sounds, see green lights but no display then toggle on the "fn" key and or try on an external monitor.