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Enjoy

Well the year 2005 was a good one in the world of video cards and graphic technologies. It’s 6months now since I purchased my Xfx7800GTx at newegg for $615, and already nVidia released the 7800GTx512MB version, albeit in limited quantity. ATi have already released there X1800xt and now there x1900xt card all with 512MBs of GDDR3, if only I held out for a few months I would have ended up getting a 512MB card instead.

Regardless I am still happy I bought my 7800GTx and it was the best card available for quite a few months, and now that all these new cards are available tempting one to upgrade, I said to myself there must be something I can do to increase performance, after all that is what overclocking is all about, and that I have learned well.

Step one, I decided to overclock and realize that my 7800gtx was artifacting all over the place without a huge bump in core speed, puzzled I decided to purchase the Zalman VF700cu for my Xfx7800GTx which comes stock at 490mhz/1300mhz.

The HSF arrived, and it was installed, I have used this same cooler before on my 6800gt which I had clocked to ultra speeds, so I expect some good performance from it. Little did I know that the cooler didn’t make any difference with the artifacts I got when I did overclock, now I was definitely bugged out! Because the temps were very well beneath 63C full load. I researched the net again and realized that the real reason for the artifacts was caused by the VGPU was not getting enough volts, and that a volt mod would take care of that.

I got on my job, ordered the parts which cost $20.US dollars shipped, got my soldering Iron ready, and printed out specs of the VGA Circuitry. After everything arrived, I followed the directions carefully and it was all done in about 15minutes. Booted into dos and adjusted voltage slightly, and loaded Windows XP SP2.

I immediately raised GPU clocks to 525MHz/1350MHz , and ran 3dmark05 firefly forest to test, with a very minor increase in voltage I was able to bump the core up to 562MHz and not worry about artifacting, temps never passed 73C while at those speeds. Here is the big increase in performance I have gained since the Voltage modification.

Set up for testing,

• AMD Opteron148
• DFI LP NF4 SLI DR
• 2x512MB OCZ PC4000 Gold VX
• Xfx7800GTx 490/1300MHz stock
• WD 36GB Raptor 10,000 RPM HD
• Silverstone Kemjin6 Case
• OCZ Modstream 2.0 525watt PSU

I really didn’t expect to get this much, but it was better than buying a new card right now. If we all did this we wouldn't have to upgrade as often. Well here are the results.

 

3D Mark 2006 - 3D Mark 2005

 

3D Mark 2003 - 3D Mark 2001SE

Aquamark 3

3D Mark 01/03 Stock/OC compare.

3D Mark 05/06 Stock/OC compare

Aquamark 3 Stock/OC compare

SM2/3 Stock/OC compare

3D Mark Tests 1- 4

Well, I think the results speak for them selves! Be careful, as this can wreck a card, if done wrongly. Once completed though, you have almost a new card, as the title suggests - nVidia 7800GTX 256MB REBORN

Forum Discussion

Part 2 - The How to!

Author Treez

Edited by Admin