After two weeks of waiting here is the replay I've got from GB's Technical support:
Dear Angel,
Thank you for supporting Gigabyte products and contacting GBT Tech Support.
At first, we are sorry for the late reply.
As to the problem you mentioned, in fact, according to AMD AP note BIOS should set to DDR333 with two dimm DDR400 or up, we still provide related option item if user try to change to DDR400. But, we will not guarantee the module/system will work properly. We are really sorry for the inconvenience and trouble you encounter because of the CPU limitation.
We have attached part of the AMD data sheet for your reference, please kindly refer to the file attached.
At last, we apology if our past service was not satisfactory. Due to the vast amounts of questions we receive daily, we understand the inconvenience of waiting for e-mail responses. If you still have any further question or suggestion about our product, please do not hesitate to contact with us. Thanks again for your understanding, and please receive our sincerely apology.
This is the Attached Image They have sent me!
******** Thank you for supporting Gigabyte products ***********
Question - 115095
From : Angel Angelov
Sent : 2004/10/2 01:23
Question : Hello
I bought a brand new MB and CPU two days ago. The GA-K8NSNXP-939 and an Athlon64 3500+ CPU! My system is having very serious problems with stability when in Dual Channel Mode!! Here is what I foind until now:
1. The Mobo will not run normaly in Dual Channel Mode with my A-Data VITESTA DDR500 Modulles even in DDR400 Standart speed with any voltage! The same goes with CANYON DDR400 Modules (with them even worse)
2. In single Channel mode the system runs perfectly well!!
3. The VITESTA DIMMs work perfectly with Soltek K8AN2E-GR and ASUS K8V-Deluxe s754 mobos plus GA-K7NNXP s462 mobo!!!
4. My ATI X800XT-PE VGA is working properly with all the mentioned mobos in t.3
5. The problems are: System restarts when reading some data from optical drives (but not every time); System returns to Desktop or restarts when Running 3D apps benchmarks or games; System gives errors in Prime95 tests; All this in Dual Channel Mode!
6. I have tried the "2T" setting in BIOS in all ot its tree states no diffrence in stability! All voltages that were availiable didn't help!
7. The PSU is Q-TEC 450W and is in perfect condition!
Please!! Can You HELP me? I gave nearly $250 for this mobo and another 450 for the CPU and now I have problems! I chose Gigabyte Mobo because of the High quality and features your products can offer!! Please don't tell me I made a Mistake!
Excuse me bad English
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Model Name : GA-K8NSNXP-939
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M/B Rev : 1.0
BIOS Ver : F4
Serial No. : 0432000007
Purchase Dealer :
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VGA Brand : ATi Model : X800XT-PE
CPU Brand : AMD Model : Athlon64 3500+ Speed : 2200MHz
Operation System : Win XP SP : 1
Memory Brand : A-DATA VITESTA Type : DDR
Memory Size : 2x 512MB Speed : DDR500
Power Supply : 450 W