Hi! I just started my Steam and update my HL today and....
OH SHI~

I started Half-Life and got 4 fps in main menu in OpenGL mode (in Software mode fps are normal) and my PC loadup to 100% (in old version there is not).
Next i joined the game and fps rises to 75 fps, but something is wrong with skyboxes...
And when i open menu during playing my fps drops down to 25 and skyboxes are... just view screenshots.

I started with -nofbo or with no both results are same.

GL INFO:
Video Card:
Driver: NVIDIA GeForce FX 5500

DirectX Driver Name:  nv4_disp.dll
Driver Version:  6.14.11.7516
DirectX Driver Version:  6.14.11.7516
Driver Date: 3 May 2008
Desktop Color Depth: 32 bits per pixel
Monitor Refresh Rate: 75 Hz
DirectX Card: NVIDIA GeForce FX 5500
VendorID:  0x10de
DeviceID:  0x326
Number of Monitors:  1
Number of Logical Video Cards:  1
No SLI or Crossfire Detected
Primary Display Resolution:  1280 x 1024
Desktop Resolution: 1280 x 1024
Primary Display Size: 13.27" x 10.63"  (16.97" diag)
                                        33.7cm x 27.0cm  (43.1cm diag)
Primary Bus: AGP 8x
Primary VRAM: 256 MB
Supported MSAA Modes:  2x 4x