Can't launch Source SDK Base 2007

Can someone help me?I have been trying to run Black Mesa but it crashes with hl2.exe has encountered a problem.And it’s not black mesa fault because other mods don’t work either and when i want to launch Source SDK Base 2007 it crashes just like Black Mesa although it should show video stress test menu.I don’t know what causes it but i tried almost everything from commands,veryfing cache to reinstalling steam and nothing.
Computer specs:
CPU: Amd Athlon™ 64 X2 Dual Core Processor 6000+
Video Card: GeForce GTX 550 Ti
RAM: 3,25 GB
Operating System: Windows XP Professional
DirectX 9.0c

Colour me curious, but could you try using these links to see if they have any effect?

steam://install/218

steam://run/218

And what are those links supposed to do?

You’re supposed to run Source SDK, not Source SDK Base 2007. Totally different things.

They’re steam shortcuts which run/install games etc in steam, first one will try to install the source sdk base 2007 (218 is the appid for it) with the second trying to start it.

Founded in 2004, Leakfree.org became one of the first online communities dedicated to Valve’s Source engine development. It is more famously known for the formation of Black Mesa: Source under the 'Leakfree Modification Team' handle in September 2004.