Unable to start up

Once I press the power button , it goes to the Acer welcome screen , but still doesn't allow me to enter BIOS, also after goes to automatic repair but fails , just restarts again.

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0

crwdns2944067:02crwdne2944067:0:

But if I change the hard drive , it goes to the Acer welcome screen and then goes to "Operation System not found" , but I plugged in this HDD to a desktop and loaded a Windows 7 OS

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

Does "loaded" mean you installed Windows 7 or that it has a copy installed? It sounds like the first hard drive has a corrupted operating system and the other drive sounds like the operating system was not correctly installed.

crwdns2934271:0crwdnd2934271:0crwdne2934271:0

crwdns2934285:0crwdne2934285:0