Try a better power supply

rower30

Distinguished
Dec 16, 2002
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I posted this in video cards, but you overclockers may be surprised at the results considering I'm NOT using any super special cooling and did have a much better than average power supply. Read on.

OK, here is the performance update to why your 12-volt video cards won't run well. Since everyone likes to talk and voice opinions, but provide little hard evidence to evaluate problems I decided to do just the opposite. I bought both power supplies and put two "good" supplies head to head in the same computer with the same software and hardware.

PROBLEM:
I installed a Radeon Sapphire 9800pro 128meg video card and several issues cropped up immediately.
-PC wouldn't hold overclocking settings.
-could only run with 64meg BIOS video aperture setting where 128meg was running well before.
- Random lock-ups in any game.
-3D mark 2001SE would not run more than a few loops without lock-ups.

I swapped out my Enermax EG465-VE 430 watt supply for a PC-Power & Cooling 510ATX-PFC. First, words can't say how impressed I am with what the Turbo Cool 510ATX-PFC power supply has done for my computer. The culprit is how modern computers are configured on the 12-volt rail.

EXAMPLE: Three SCSI hard drives, a P4 CPU, several fans, a CD-ROM and a high-end video card were just too much on the 12-volt rail. My EG465-VE 430 watt Enermax supply seemed to fit the 300 watts or better requirement for the new video card but the computer was at odds with that recommendation.

My room is typically 80F to 85F during the day and the turbo Cool supply simply ignores the internal PC temperature and things simply run flawlessly. 3D Mark 2001 SE ran for four hours straight and not a single hic-up. The CPU is showing 60C and the Motherboard is showing 43C. Too
hot? Intel's site download to PDF format(http://www.intel.com/design/pentium4/datashts/298643.htm) calls for a P4 temperature max of 70C-75C so I'm still well below anything that would bother the CPU or Motherboard. I have to conclude that most of the CPU and case cooling efforts are misguided most of the time since my actual experience seems to say that the CPU is fine as a can be running at 60C, but it needs clean power, something the Enermax couldn't do at 40-45C. So, people are trying to lower the POWER SUPPLY temperature, without knowing it, to avoid the loss of clean and/or saggy power at elevated temperatures. That's too bad, too. It cost them a lot more to mess with liquid cooling and / or huge heat sinks than buying a 40C capable power supply.

To prove my point, I overclocked my CPU from 2.4GHz to 2.7GHz (150MHz FSB), the PCI / AGP bus to 37.5 / 75MHz, and the video card's VPU from 380MHz to 400MHz (memory is left at stock settings). Guess what? It still runs flawlessly with internal case temperature of 49C or about 120F! The
Motherboard reads about 43C so my thermometer seems about right. 3D Mark 2001SE loops indefinitely (over 4 hours).

If you read the news groups, how can you achieve good overclocking with high temperatures? How can this be? My temperatures are so high I should hang my head in shame, or at least that's what the "zero C" boys would have you think. What do I think?
A PC's CPU / VPU DOESN'T SEEM TO CARE HOW HOT IT IS, AS LONG AS IT'S IN SPEC, BUT IT DOES CARE WHAT THE VOLTAGE RAILS ARE! Is your power supply in spec?

If you have a 12-volt video card and a P4 processor, and you are having problems, check your power supply temperature. If the exhaust fan temperature is any where over 30C, I'll bet you can't muster the drive rail currents and voltages to properly run your card.

Very few power supplies are really capable at 40C (about where a modern PC will run). Your other option is to buy the biggest "cheap" supply you can find and hope it doesn't sag so much at temperature that you fall back into trouble.

Regards,
rower30@earthlink.net
 

svol

Champion
With such an setup a 430W PSU would probably already be running near its max even in normal temps.

I love my Delta 60HP 7000 RPM fan that puts out more dB then CFM :eek: