Low FPS on Garry's Mod

[chaoss1986]

All other games seem to work on maximum settings, but Garry's Mod seems to run really slowly, changing the quality settings doesn't really help, specs are...

Operating System
MS Windows 7 Ultimate 64-bit
CPU
Intel Xeon W3570 @ 3.20GHz 61 °C
Bloomfield 45nm Technology
RAM
12.0GB Dual-Channel DDR3 @ 668MHz (9-9-9-24)
Motherboard
ASUSTeK Computer INC. P6T6 WS REVOLUTION (LGA1366) 50 °C
Graphics
Sony GDM-FW900 (1920x1200@120Hz)
DELL U2410 (1920x1200@59Hz)
DELL 1708FP (1280x1024@60Hz)
NVIDIA GeForce GTX 470
NVIDIA GeForce GTX 470
Hard Drives
250GB CRUCIAL_CT256M225 ATA Device (SATA)
250GB CRUCIAL_CT256M225 ATA Device (SATA)
977GB Western Digital WDC WD1002FAEX-00Y9A0 ATA Device (SATA) 33 °C
977GB Western Digital WDC WD1002FAEX-00Y9A0 ATA Device (SATA) 31 °C
Optical Drives
HL-DT-ST DVD-RAM GSA-H30N ATA Device
ATAPI iHAS124 B ATA Device
Audio
SB X-Fi Xtreme Audio

[Cheesemonkey]

define slowly.

there's slow as in "9 fps can't do shit" and then there's "it only runs at 50 fps that's too slow for my rig!!!" which happens too often