Why is this Asus motherboard rejecting RAM?

2048Megabytes

2048Megabytes

Active Member
I was running the following with no issues:

Motherboard: ASUS A7N266-VM/AA ACPI BIOS Rev 1006 SOCKET A (462)
Motherboard Features: 2 x 184-pin Dual In Line Memory Module sockets
Processor: AMD Athlon XP 2200+ (1.8 Gigahertz)
Random Access Memory: 768 megabytes (256 megabyte PC-2700 Mushkin and 512 megabyte PC-3200 Super Talent)
Power Supply: GigaCase 200 Watt, 12 Volt
Operating System: Windows XP

Whenever I would try to swap the 256 megabyte stick out that came with the system and switch it with a 512 megabyte PC-3200 RAM stick it wouldn't work. The motherboard speaker would start beeping and the system would not boot up. I tried four different sticks of PC-3200 512 megabyte memory (three different brands) with the same results. These memory sticks would work in the second slot for memory but not the first.

Crucial.com states that this motherboard accepts PC-3200 memory and has a maximum capacity of 1 gigabyte of RAM with a maximum of 512 megabytes per memory slot. Why is this motherboard rejecting all memory in the slot closest to the processor except the stick of memory it came with?
 
The max speed supported for the micro atx model there is 266mhz not 333mhz as you would see with PC2700 memory. DDR400 memory won't always backclock two speeds but only down to 333 to then run at 333mhz.

Mushkin is a great brand for the older Asus boards since it does backclock from 333 to 266mhz easily. Plus going from 333 down to 266mhz is only one speed backwards not two as seen with DDR400 memory. The information seen at Crucial is apparently off!
 
The specifications show 200/266mhz meaning PC2100 not PC2700 is the fastest supported. You've been trying to run faster memory and this where the problem is since you are trying dimms that are two speeds faster then the board supports.

With varying makes and model boards as well as brands and types of memory some simply won't backclock that far on some boards. Plus you have neen mixing memory there not knowing the actual timings for each dimm. Your best move is to match a pair of PC2100 512mb dimms by the same brand for the best results.
 
if the module works in the other dimm slot, then the board must somehow support it.

how many chips do you have on the 512MB module?
 
The nForce chipset will support both single and dual sided dimms. You just can't mix the two types there either. The Mushkin dimm is actually DDR266 while the Super Talent and others are DDR400. The Mushkin is running at the speed the board supports since it came with the system. It's either backclocking the one speed slower or is PC2100 memory not PC2700.
 
I know the Mushkin memory is a 256 megabyte PC-2700 stick in the motherboard. It says it on the label and when I ran CPU-Z it identified it as PC-2700. On boot up it also identified it as DDR 333 memory.

The Mushkin 256 megabyte PC-2700 memory module came with the system when I bought it from Totally Awesome Computers around the year 2002. I would like to try a 512 megabyte PC-2700 in the board sometime and see if it works.

Thanks for the information.
 
For that board I would stay with the Mushkin so you would see it backclock to the 266mhz max the board supports. On the old Asus A7N8X Deluxe the matched pair of Corsiar xms series DDR400 PC3200 dimms would backclock to 266 when the fsb was lowered down from 200 ro 133 in the bios.

The other memory here is lower quality and not worth the hassle. First take a look at the 256mb Mushkin to see if that is a single or dual sided dimm. Some older boards simply won't run a dual sided dimm. That's a dimm seeing a row of ic chips on both sides of the dimm itself.
 
I just looked at the Mushkin memory module and it is double sided. I think it has to be because the motherboard was made for PC-2700 memory.
 
The specifications on the board show PC1600 and PC2100 with the 200/266mhz fsb. What is working there is that the 333mhz memory is simply running at 266mhz. The Asus support is the place to go if you don't have the user manual to see the specifications there.



The only two manuals from that series board are from the one there(A7N266-VM) and the A7N266-VM/SE model. But that clearly shows 266 in the model number itself.
 
I couldn't a model listed as VM/AA while finding the VM and VM/SE models. But the giveaway is in the A7N266(266=266mhz) part of the model number. That was prior to the A7N8X Deluxe and A7V models supporting DDR400 PC3200 memory. Since the board supported the faster memory I could lower the fsb down or see it lowered when using the XP2600+ that was first bought for the board here.

The XP3000+ saw 333 with the final move to the XP3200+ to see the full benefit of the 400mhz there. You have an older model that runs the slower memory. The first thing to remember when going to buy memory is first look over the actual specifications so you don't end up buying the wrong type or speed.
 
tyttebøvs said:
so what was the specs on that super talent module?
Click to expand...

You didn't read the intial post where that was mentioned as being DDR400 PC3200 memory. The problem there is that it won't backclock to the 266mhz speed supported by that model board. Some quality brands like Corsair, Kingston, OCZ, Crucial, and a few others may run at 266 depending on type and perhaps manually setting the dram timings as well as voltage.
 
but it will backclock, if it sits alone, in the second slot?

- the full specs on a module includes more than just size and max rated frequency without overclocking
 
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When mixing a faster dimm with an existing slower dimm the faster one is installed in the first slot like A1 or slot #1 according to the board's manual. That's the actual recommendation seen all over. But there's a problem there with it only working in the second not first slot. Bad memory slot? not as likely as incompatible memory.
 
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