Regression in Dapper & Edgy] Crashes at Boot

My screen randomly goes black and then my hard disk light just stays on constantly. My monitor says "no signal". This mostly happens at the same time as the splash screen should appear at boot time but also happens when I'm working in Gnome (usually when I open an application). This problem has been happening to me with more recent kernels for Dapper and the one that comes with Edgy Beta.

When I use the version of Dapper that installs of the CD it works fine and this problem doesn't occur.

Due to the problem I've been unable to update to the latest version of Edgy.

Here is some information about my hardware and I can provide more if required:

cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 2
model name : Intel(R) Pentium(R) 4 CPU 3.20GHz
stepping : 9
cpu MHz : 3208.232
cache size : 512 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe cid xtpr
bogomips : 6416.98

My lspci result:

0000:00:00.0 Host bridge: Silicon Integrated Systems [SiS] 661FX/M661FX/M661MX Host (rev 11)
0000:00:01.0 PCI bridge: Silicon Integrated Systems [SiS] SiS AGP Port (virtual PCI-to-PCI bridge)
0000:00:02.0 ISA bridge: Silicon Integrated Systems [SiS] SiS964 [MuTIOL Media IO] (rev 36)
0000:00:02.5 IDE interface: Silicon Integrated Systems [SiS] 5513 [IDE] (rev 01)0000:00:02.7 Multimedia audio controller: Silicon Integrated Systems [SiS] Sound Controller (rev a0)
0000:00:03.0 USB Controller: Silicon Integrated Systems [SiS] USB 1.0 Controller (rev 0f)
0000:00:03.1 USB Controller: Silicon Integrated Systems [SiS] USB 1.0 Controller (rev 0f)
0000:00:03.2 USB Controller: Silicon Integrated Systems [SiS] USB 1.0 Controller (rev 0f)
0000:00:03.3 USB Controller: Silicon Integrated Systems [SiS] USB 2.0 Controller0000:00:09.0 Ethernet controller: Marvell Technology Group Ltd. Marvell W8300 802.11 Adapter (rev 07)
0000:00:0a.0 Communication controller: Agere Systems V.92 56K WinModem (rev 03)
0000:00:0d.0 FireWire (IEEE 1394): VIA Technologies, Inc. IEEE 1394 Host Controller (rev 80)
0000:00:0e.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10)
0000:01:00.0 VGA compatible controller: nVidia Corporation NV34 [GeForce FX 5500] (rev a1)