I cant get into bios on acer veriton l410 pc

So you are wanting to upgrade the video card im guessing using the pci express slot. You will need go into the bios and disable the on-board graphic card and tell it to look at the pci-e slot for video boot.

Could be bad RAM, motherboard, hard drive, etc. Any beeps during startup? They would tell you what is wrong (with a Google search).

Download Driver Acer Veriton L410 Desktop for Windows 7
http://global-download.acer.com/GDFiles/Driver/Lan/LAN_Realtek_6.191.0305_Vistax86.zip?acerid=633645067608821678&Step1=Desktop&Step2=Veriton&Step3=Veriton%20L410&OS=V10&LC=en&BC=Acer&SC=EMEA_27

or
wifi
http://global-download.acer.com/GDFiles/Driver/Wireless%20LAN/WLAN_Atheros_7.3.1.42_Vistax86.zip?acerid=633645067517717094&Step1=Desktop&Step2=Veriton&Step3=Veriton%20L410&OS=V10&LC=en&BC=Acer&SC=EMEA_27

or

wifi
http://global-download.acer.com/GDFiles/Driver/Wireless%20LAN/WLAN_Broadcom_4.102.28.4_Vistax86.zip?acerid=633645067553909326&Step1=Desktop&Step2=Veriton&Step3=Veriton%20L410&OS=V10&LC=en&BC=Acer&SC=EMEA_27

Sounds like it might be a Hard Drive Issue if you have heard any strange noise comming from the hard drive the Just think about replacing it with a new one .
If I can be of futher assitance feel free to contact me by posting on this page

Have you tried this:

1) Reboot your computer and Enter Setup.
2) Click on the tab labeled PC Health Status.
3) Find the feature labeled Chassis Intrusion Detect, and change the status to RESET
4) Press the Esc key to access the main menu and then use the arrow keys to choose Save & Exit from the menu.
Do NOT use the F10 key. If you use F10 key to Save & Exit, it does not properly reset this feature!!!!
If you wish to set the Chassis Intrusion Detect feature so it never generates a warning message at boot, follow these instructions
A) Reboot your computer a 2nd time and Enter Setup.
B) Click on the tab labeled PC Health Status again..
C) Find the feature labeled Chassis Intrusion Detect, and this time change the status to DISABLED
D) Press the Esc key to access the main menu and then use the arrow keys to choose Save & Exit from the menu.
Do NOT use the F10 key. If you use F10 key to Save & Exit, it does not properly reset this feature!!!!

Sound you are trying to get into the BIOS, some use key F2,F8, or F10, it will say very fast what the correct key is, it might be very fast.

The first item is the key or key combination. The second is the model of PC or the maker of the BIOS. You'll see some companies listed many times, with different keystrokes. That's normal. (It's not that manufacturers can't make up their minds. It's just that they change suppliers and use different BIOS setups.)
Delete: AMI or Award BIOS.
Esc: Toshiba
F1: Toshiba; Phoenix; some IBM PS/1 models.
F10: Compaq.
F2: NEC.
Insert: IBM PS/2.
Tab: eMachines.
Reset button (press twice): Some old Dells.
Ctrl-Alt-+: Various computers.
Ctrl-Alt-?: Some old IBM PS/2 models.
Ctrl-Alt-Enter: Some Dells, others.
Ctrl-Alt-Esc: AST, Tandon, others.
Ctrl-Alt-Ins: Zenith PCs, Phoenix BIOS.
Ctrl-Alt-S: Phoenix BIOS.
Ctrl-Alt-Shift with Del (on number pad): Olivetti.
Ctrl-Esc: Many PCs.
Ctrl-Ins: Some IBM PS/2s.
Ctrl-S: Phoenix BIOS.
Ctrl-Shift-Esc: Tandon

find a file with .exe extension, usually "setup.exe" or something to that effect.

depending on ur virus scanner, it could be searching for viruses during start up