Stock CPU settings fail Prime

[silentvois]

Before I begin, here's the specs:

Athlon 64 X2 3800
DFI Lanparty Ultra D
OCZ Platinum 2gb 2-3-2-5
Enermax EG565 (535W PSU)
EVGA 7800GT
2 Hardrives
1 DVDRW
4 x 120mm fans, 1 x 92mm fan

Overclock info:
CPU 2.0ghz to 2.41 ghz (10x241) Voltage = 1.43V
RAM at 241 mhz (166 divider) = ~201mhz

This has been working without any problems and passed prime for 20hrs in my old location. Now that I'm at a new location I noticed that the 2nd cpu core has been failing prime after 2 mins at 2.41 ghz overclock but the 1st core runs fine. Tried upping the voltage in increments all the way past 1.5V and still failing prime in 2 mins. I then put everything back to stock speeds (2.0ghz) and default auto detect voltages and even a forced 1.4V and up and the 2nd core still fails prime.

What I'm thinking is the electrical signals aren't stable in my new place that's causing this. Anyone have any similar experiences that can justify this problem? I'm also looking for a cheap UPS or line conditioner that'll clean up the dirty signals. Anyone got any suggestions? I'm looking to spend about $50 USD.

 

[pm]

If this is the problem, a cheap UPS should do it. It seems a little unlikely, but possible I suppose.

I used to have a problem in our old house (aluminum wiring <sigh>) where turning on my 22" NEC monitor would cause the lights to dim in the room and occassionally would cause the computer to reboot. I bought a cheap UPS - the cheapest that I could find and put the monitor and computer onto the battery backup input and it completely solved the problem. The lights were all rock solid, the computer has never had any problems either. Then I moved moved houses and our new house is wiring with 12g copper.