P35 motherboard on the fritz, upgrade mobo or full upgrade?

Dilemma: Replace my mobo only or replace mobo, cpu and RAM?

My Gigabyte GA-P35-DS3L rev2.0 board has gotten a bad case of the cold boot-itus. It's to the point of rediculous now. Whenever I turn my computer on in the morning it refuses to even post, just the fans go full speed and it sits there. I have to cycle the power with the PSU switch on the back multiple times for it to even come on, and then the BIOS settings are reset.

I ran memtest over night and 0 errors.

Based on the system below, do you think its wise to just replace my motherboard, or are PC games currently already maxing out my specs?
I've been out of the loop of gaming for a while but looking to make a return.

My current system:

GIGABYTE GA-P35-DS3L LGA 775 Intel P35 ATX All Solid Capacitor Intel Motherboard - Retail
http://www.newegg.com/Product/Prod [...] 6813128059

Intel Core 2 Duo E6750 Conroe 2.66GHz LGA 775 65W Dual-Core Processor Model BX80557E6750 - Retail
http://www.newegg.com/Product/Prod [...] 6819115029

XFX PVT80GGHD4 GeForce 8800GTS 320MB 320-bit GDDR3 PCI Express x16 HDCP Ready SLI Supported Video Card - Retail
http://www.newegg.com/Product/Prod [...] 6814150173

Crucial Ballistix 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory Model BL2KIT12864AA1065 - Retail
http://www.newegg.com/Product/Prod [...] 6820148069

OCZ StealthXStream OCZ600SXS 600W ATX12V / EPS12V SLI Ready Active PFC Power Supply - Retail
http://www.newegg.com/Product/Prod [...] 6817341010

The PSU is less than 2 years old, along with everything else. I've been searching for resolutions to this problem for over a week and the p35 chipset has a well complained about cold boot issue that effects different brands of mobos.

I don't really have a hard number for my budget, I go for the best price to performance ratio hardware. My two biggest factors in what I choose is stability and price. 2 fps difference is less important to me than a rock solid system.

but if the problem only happens during a cold boot, how would that be effected by the NB being too hot?

Is there an updated BIOS that corrects the issue?

I will give my cmos battery a look. My date and time have never been reset so far, which is good I suppose.

Without fail every morning I would have this problem, but last night I tried raising the voltage of the northbridge chipset by +.1 and this morning my PC booted up with no issue. Not sure if this was just a fluke or if tonight when I get home from work if it will boot right up again without issue. I will report what happens.

Thanks

Did the voltage increase stay ?

the voltages stayed even after the several power cycles. i have never overclocked my cpu but yesterday i tried that (just a small oc 2.66 o 2.75ghz) and this also stayed.. i'm thinking it's not a cmos battery issue if my settings stick and i've never had date or time get screwed up. i'm going to see if my ram settings revert back to auto, although i'm not sure what good that will do since i've ran a memtest overnight with no errors. i'm starting to think something on the motherboard is going bad that only effects cold boots. not sure if my power supply could effect this, it's a pretty good one.