AMD FX74s on regular dual opteron 1207 motherboards

[lav]

Guys,

Do you know if there is a possibility to combine a regular dual socket 1207 Opteron server/workstation motherboard with a pair of FX74s instead of Operon 2xxx? Do Tyan, Supermicro, ASUS offer bios updates to recognize the new CPUs? What do you guys know? I'm thinking that it should theoretically work, both are socket 1207, although the reliance on registered memory for Opteron platform might introduce some problems... I don't know, I was just thinking. I really want a motherboard that with more RAM slots than PCI express slots. The new CPUs will open the possibility of using cheaper non-registered RAM. It seems the web doesn't offer a straight answer.

Peace,
Lav

 

[BaronMatrix]

Guys,

Do you know if there is a possibility to combine a regular dual socket 1207 Opteron server/workstation motherboard with a pair of FX74s instead of Operon 2xxx? Do Tyan, Supermicro, ASUS offer bios updates to recognize the new CPUs? What do you guys know? I'm thinking that it should theoretically work, both are socket 1207, although the reliance on registered memory for Opteron platform might introduce some problems... I don't know, I was just thinking. I really want a motherboard that with more RAM slots than PCI express slots. The new CPUs will open the possibility of using cheaper non-registered RAM. It seems the web doesn't offer a straight answer.

Peace,
Lavn

I believe that's a no since the Opteron boards will use ECC and QFX has non-ECC IMC(internal memory controller). Just wait for a few months and mobo prices should stabilize and more options should com around.

 

[Apple_Fritters]

"We will get to how this impacts your upgrade path and CPU costs later, but for now just know that Quad FX only works with 1207-pin Athlon 64 FX CPUs (Opterons are prevented from working in the BIOS). "

http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2879&p=2

This only states that Opterons won't work on a QuadFX motherboard. Vice Versa? Maybe all it takes is a BIOS update. But really, why?

 

[Apple_Fritters]

Since the memory controller is integrated, shouldn't that determine the type of ram. Maybe there's other issues? Voltage? Slot? I'm not familiar with Registered memory.

 

[lav]

I'm under the impression that the memory controller should not matter. The controller is on the CPU anyway, so if you change the CPU, the key remains in having a "neutral" BIOS that doesn't do many checks regarding the ECC/reg status of memory. That's just an opinion, I might be missing something. The platform is kind of new and the geeks outhere haven't tried all the combinations... Anyway, I just want a cheap motherboard, even non-SLI but with 8 memory slots. The current ASUS is a non-starter for me.

Lav

 

[MU_Engineer]

DDR2 memory is DDR2 memory, physically. Regular unbuffered DDR2, registered ECC DDR2, and even DDR2 FB-DIMMs all have 240 pins and use 1.8 volts. However it is the signaling methods that differ and regular DDR2 won't work in an ECC server board and ECC server RAM won't work in boards that take normal unbuffered memory. I know this as I have accidentally gotten sticks switched up and put ECC memory in a desktop and unbuffered DDR2 in servers. The memory physically fits but the computer won't boot. It just gives off a series of long beeps or and/or a memory error message.

With AMD CPUs, the memory controller is specific for a certain type of RAM, as far as I know. I do know that with Intel CPUs, the chipsets, particularly the northbridge (MCH) are what determine the RAM type used and that the same CPU can use different kinds of RAM dependent on what chipset the board has on it. 400 FSB Pentium 4s could use either RAMBUS RDRAM, PC100 SDRAM, or DDR 266, dependent on which chipset its board had.

 

[lav]

Good information...Although I still somehow suspect the BIOS for your mishap with the computer non booting. Also, back in DDR (not DDR2) times, there were AMD socket 939 motherboards like my Asus A8V deluxe that would take either ECC or non-ecc memory and it would handle it. Of course the ECC feature was used only if you put a Opteron socket 939 with a correct ecc friendly memory controller. At least that was in theory, I personally haven't tried it. Also, you talked about signaling. I'm under the impression that it's the CPU that does the signalling on AMD platforms. As you said, they don't have a northbridge like Intel's that is the memory controller, so if the CPU signals right, the voltages and physicall socket for DDR2 are the same and if BIOS doesn't do stupid checks, in theory it should work. Am I missing something?

Lav

 

[BaronMatrix]

Since the memory controller is integrated, shouldn't that determine the type of ram. Maybe there's other issues? Voltage? Slot? I'm not familiar with Registered memory.

That's the issue. The QFX uses non-ECC which means the IMC can't operate on an Opteron board with ECC.

 

[MU_Engineer]

Buffered memory and unbuffered memory have different physical characteristics. There is an extra register between the memory cells and the memory controller (off the module) that in delays the accesses 1 clock in buffered memory that's absent on unbuffered memory. So a memory controller set up to only work on unbuffered RAM would be out of sync with a buffered DIMM and vice-versa. ECC RAM uses an error-correcting code in the RAM modules and this does not affect RAM clock sync. So it's entirely possible for boards/chips that use unbuffered memory to use ECC memory as well. Most ECC chips are also buffered, so I have not been able to try this out myself. But it's possible. In fact, Intel's 975X chipset can use standard unbuffered RAM or ECC unbuffered RAM. I am not sure about AMD chips.

 

[lav]

Yes...you are right, it's the buffered/non-buffered issue here at stake. But I want to pair FX 74s with NON-buffered, consumer grade DDR2 memory, on the dual opteron motherboard. That was my question. I'm looking for a silver bullet low cost solution. In this config, the non-buffered integrated memory controller on the CPU and the non-buffered memory should theoretically work. I guess I have to wait and see. Unless there is something on motherboard that is hardwired for buffered memory signaling.

Lav