While playing Team Fortress 2 the game will periodically lock up between 2 to 10 seconds. This has been happening for a while, attached is a older screenshot of what the net_graph is showing during these locks.

Processor Information:
Vendor: GenuineIntel
CPU Family: 0x6
CPU Model: 0x1a
CPU Stepping: 0x5
CPU Type: 0x0
Speed: 3068 Mhz
8 logical processors
4 physical processors
HyperThreading: Supported
FCMOV: Supported
SSE2: Supported
SSE3: Supported
SSSE3: Supported
SSE4a: Unsupported
SSE41: Supported
SSE42: Supported

Network Information:
Network Speed:

Operating System Version:
Linux Mint 14 Nadia (64 bit)
Kernel Name: Linux
Kernel Version: 3.5.0-40-generic
X Server Vendor: The X.Org Foundation
X Server Release: 11300000
X Window Manager: Marco
Steam Runtime Version: steam-runtime-release_2013-09-05

Video Card:
Driver: NVIDIA Corporation GeForce GTX 680/PCIe/SSE2

Driver Version:  4.3.0 NVIDIA 325.15
OpenGL Version: 4.3
Desktop Color Depth: 24 bits per pixel
Monitor Refresh Rate: 59 Hz
VendorID:  0x10de
DeviceID:  0x1180
Number of Monitors:  1
Number of Logical Video Cards:  1
Primary Display Resolution:  1440 x 900
Desktop Resolution: 1440 x 900
Primary Display Size: 16.14" x 10.08"  (19.02" diag)
                                        41.0cm x 25.6cm  (48.3cm diag)
Primary Bus: PCI Express 16x
Primary VRAM: 2048 MB
Supported MSAA Modes:  2x 4x 8x 16x 

Sound card:
Audio device: VIA VT2020

Memory:
RAM: 16048 Mb

Miscellaneous:
UI Language: English
LANG: en_US.UTF-8
Microphone: Not set
Total Hard Disk Space Available: 275247 Mb
Largest Free Hard Disk Block: 133006 Mb