|"Lenovo Y500 Laptop"|
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" I have installed window xp "
XP doesn't have the drivers built in for most things that first came out after XP was first released, circa 2001, and it doesn't have some of the drivers built in for things made before that.
Whenever you load Windows from a regular Windows CD (or DVD) from scratch, after Setup is finished you must load the drivers for the mboard, particularly the main chipset drivers, in order for Windows to have the proper drivers for and information about your mboard hardware, including it's AGP or PCI-E, ACPI, USB 2.0 if it has it, and hard drive controller support. If you have a generic system and have the CD that came with the mboard, all the necessary drivers are on it. If you load drivers from the web, brand name system builders and mboard makers often DO NOT have the main chipset drivers listed in the downloads for your model - in that case you must go to the maker of the main chipset's web site, get the drivers, and load them.
XP does NOT have at least some of the drivers for your computer built into it.
Have you installed XP drivers for your model ?
Usually you must get the video drivers from the Lenovo web site for your model. The drivers for your built in display (monitor) are usually embedded in the video drivers.
If you haven't installed other XP drivers available for your model you will need to install those too.
When you look at Display Propetrties - Settings....
(RIGHT click on a blank part of your main desktop screen - Properties - Settings)
........what does it say there ?
If the proper video drivers have been installed, it should say
xxxx monitor or similar (something other than Default or Unknown), on Intel xxxxx or Nvidia xxxx or Radeon xxxx or similar
If you don't see Intel xxxx or Nvidia xxxx or Radeon xxxx or similar, you will probably NOT see two icons that look like monitors that represent the displays. You need to install then proper video drivers, the proper way !