Asus M3A79-T Deluxe

sir-les-mp · 8 Oct 2010 at 02:26

I'm now at the end of my tether with this board as it permantly clocks my cpu @ 800Mhz.
I currently have an AMD Athlon X2 5000 in it which should run at 2200Mhz, before you all gasp at how low that is it is one of the Phenom II Denab Processor's when combined with the correct AMD motherboard unlocks to a Phenom II FX5000 Quad core CPU.
This i have done via the bios and it is indeed showing up in the bios as an FX5000 with the full 6Mb level 3 cache to boot, and also when checking with device manager within Windows ( in this case Win XP Pro 32bit) it is also reported as an FX5000 Processor running @ 2200Mhz.
However when running CPUId, Core Temp etc the CPu is being reported as running @ 800Mhz this being calculated with the FSB of 200Mhz and a multiplier of 4.

I do not have cool'n'quiet enabled in either the bios or windows nor do i have C1E enabled either, so as far as i can tell the cpu SHOULD NOT be downclocking to 800Mhz.
I have also tested by setting the cpu to stock in the bios i.e by not unlocking the extra core's again within windows the base speed is reported as 800Mhz
I also tested the motherboard with my known working Quad core a Phenomn II 940 which also sufferred the downclocking issue.

To solve the issue ive tried various versions of the bios and various differrent settings within the bios all to no avail.
I even bought a second version of this motherboard from the bay which turned out to be non working, but i did try by swapping over the bios chips from one board to the other the second board still did not work and the differrent bios chip from it does work and proved that a corrupt bios chip was not to blame with my current board.
Ive also tested it with 2 different power supplies, My 1100Watt Tagan which runs my main Rig and my spare Silverstone Strider 750Watt which it is currently running from. So i can rule out lack of power being an issue.

I have even went to the trouble of contacting Asus with the issue and trying out all their suggestions which took months only to be told to take the mobo back to the store i bought it from i was hoping they would accept it back for RMA directly.

So now at present im stuck with a Partially working motherboard in that it runs all the hardware ive installed in it but will only run the CPU at 800Mhz.
What im looking to find out is if anyone here knows what chip on the motherboard controls the FSB, Multiplier and Vid Voltage for the CPU as one soloution could be to transplant the chip from the non working motherboard to this one.
There are pro's and cons to this i know
Pro would be i get 1 good fully working motherboard from basically 2 faulty ones
It would only cost me some time and patience.
Cons
I could end up with 2 extremly large paper weights and a bill for a new motherboard which supports AM2+ cpu and DDR2 Dram multiple PCI-E slots and the abiltiy to unlock my dual cores full potential

Unless anyone here has another idea ive not tried yet.

kedge · 8 Oct 2010 at 11:44

sir-les-mp said:
I'm now at the end of my tether with this board as it permantly clocks my cpu @ 800Mhz. I currently have an AMD Athlon X2 5000 in it which should run at 2200Mhz.

It might not be the motherboard at fault here, it could possibly be the chip?. Does the x2 5000+ run at default speed 2200 ok?. And 11 x 200 does not work?.

Edit: Sorry i just noticed you tried at stock. You have the latest bios i presume?. I have one of these motherboard as a backup, but when i used it, it really was fantastic board but i haven't tried a x2 5000+ though, only a phenom x4 and a phenom II 965.

kedge · 8 Oct 2010 at 11:59

sir-les-mp said:
What im looking to find out is if anyone here knows what chip on the motherboard controls the FSB, Multiplier and Vid Voltage for the CPU as one soloution could be to transplant the chip from the non working motherboard to this one.

You can download the m3a79-t deluxe manual from asus. The chipset is amd 790FX / SB750. AMD Athlon X2 5000 unlocked into Phenom FX-5000. AMD Athlon X2 5000 unlocked to Phenom FX-5000 - [H]ard|Forum

sir-les-mp · 8 Oct 2010 at 13:22

kedge said:
You can download the m3a79-t deluxe manual from asus. The chipset is amd 790FX / SB750. AMD Athlon X2 5000 unlocked into Phenom FX-5000. AMD Athlon X2 5000 unlocked to Phenom FX-5000 - [H]ard|Forum

Ive got 2 copies of the manual and have studied them thorouly but cant find out whch chip on the motherboard controls the settings for the cpu.
If i could find out which chip on the motherboard controlled the HTT/FSb, CPU Multiplier, and also the CPU VID voltage as i belive this could be part of the issue as it reports the VID as 0.9775 V.

As for the motherboards Chipset i was aware of this as this was the reason i bought it to try and Clock my 940 to a stable overclock as my current board which has the SB600 Southbridge chipset just wont clock my cpu .
But when i run into the clocking issue with the new board i bought the X2 5000 as a spare test cpu for a measily £30 brand new and after reading about all the others that have been found to unlock and this one also aparently doing so also i thought id got my self a very cheap Quad core system.
I would love to get this board working properly and not have to spend anymore money to get the full potential out of the X2 5000 ive got currently running in it.

Hagar · 8 Oct 2010 at 14:02

Have you tried running prime95 with the default bios settings and checking CPUId, then doing the same with your unlocked settings?

sir-les-mp · 8 Oct 2010 at 15:37

nkata said:
Have you tried running prime95 with the default bios settings and checking CPUId, then doing the same with your unlocked settings?

Tried three differrent cpu stress testers and non of them would up the core speed to stock of 2200Mhz when being run at 100%

i used Prime 95, OCCT and also intel burn tester as well.

sir-les-mp · 16 Oct 2010 at 20:30

Well ive bitten the bullet and bought yet another one of these motherboards in the hope of Third Time Lucky.

Shad · 17 Oct 2010 at 20:03

You're not alone! I'm having exactly the same issue with my board, but with a PII 940 and 965. If you want a 4th dodgy M3A79-T board for your collection, I expect mine will be available soon.

Electronic Dave · 17 Oct 2010 at 22:25

I don't know if this will help in anyway, seems very strange guys as I've had my M3A79-T with a X4 940 since first launch (Feb 2009) and haven't had these issues. I do have Cool 'n' Quiet enabled on mine and have a modest overclock.

When I first had the board (under XP) I noticed that I had to choose 'minimal power managemant' to get Cool 'n' Quiet to work properly (i.e. to get the CPU to run at 800MHz) as well as turning it on in the BIOS. I spent ages wondering why it wouldn't drop down in CPU-Z. If you select 'office/desktop' (the default) it doesn't work and the CPU always runs at stock (3.0Ghz). Mine did happily clock away at 3.0-3.4GHz and no drops until I decided to use Cool 'n' Quiet.

Have you got the AMD CPU Driver installed? (available as a download from AMD's website). This maybe required as you are using Windows XP after all...its not required for Vista/7...perhaps as you've unlocked it, could there be an OS issue? Does your POST screen show the current processor speed (i.e. 2.2GHz?) if so its more likely a Windows issue with Cool 'n' Quiet / CPU.

sir-les-mp · 18 Oct 2010 at 22:23

Electronic Dave said:
I don't know if this will help in anyway, seems very strange guys as I've had my M3A79-T with a X4 940 since first launch (Feb 2009) and haven't had these issues. I do have Cool 'n' Quiet enabled on mine and have a modest overclock.

When I first had the board (under XP) I noticed that I had to choose 'minimal power managemant' to get Cool 'n' Quiet to work properly (i.e. to get the CPU to run at 800MHz) as well as turning it on in the BIOS. I spent ages wondering why it wouldn't drop down in CPU-Z. If you select 'office/desktop' (the default) it doesn't work and the CPU always runs at stock (3.0Ghz). Mine did happily clock away at 3.0-3.4GHz and no drops until I decided to use Cool 'n' Quiet.

Have you got the AMD CPU Driver installed? (available as a download from AMD's website). This maybe required as you are using Windows XP after all...its not required for Vista/7...perhaps as you've unlocked it, could there be an OS issue? Does your POST screen show the current processor speed (i.e. 2.2GHz?) if so its more likely a Windows issue with Cool 'n' Quiet / CPU.

It made no difference whether i unlocked the current cpu or not as it still auto downclocked to 800Mhz.
i Had also used my Phenom II 940 Quad core cpu as well with the same downclocking present.
As for Windows XP i also tried Windows Vista Ultimate and Windows 7 Ultimate as well.

When i use the CPU's in my MA32-MVP Deluxe mobo they both run at full speed although this being a mobo with the AMD SB600 chipset it is unable to unlock the extra core's.

sir-les-mp · 20 Oct 2010 at 19:05

Well the new M3A79-T Deluxe arrived today
Installation was pretty painless for once
And it seems to work fully in fact im currently stress testing the Phenom II X2 5000 which is fully unlocked now and currently clocked at 2700Mhz