Asus A8N-SLI and getting 4x512MB or 2x1GB?

[imported_BIOSMonkey]

I am on the verge of buying parts for a new system, but am puzzled about the memory configuration.

In my current system (the one I am replacing) I have 2x512 of Corsair XMS PC3200 Low Latency (2-3-2-6). My intent was to take these sticks, get another two of the same type and put a total of 2GB in the new machine (needed for Photoshop).

However, when researching parts I came across a lot of talk regarding performance timings and 2 versus 4 sticks. In particular, the fact that some motherboards reduce timings/clock to DDR333 when running 4 sticks of DDR memory.

I could not find reference to this fact in the A8N-SLI manual....

Does this board support four sticks without reduced timings? As an alternative I was going to just get 2 Geil 1GB sticks of the value 3200, but I hate to waste the low latency memory I have. Assuming this board does NOT reduce timings, is there any other reason why two sticks better than four??

PS - the two sticks of Corsair (1gb total) are the same price as 2gb of the Geil! Maybe I should not worry so much about timings and just get the Geil?

 

[century child]

That's a tough one to call. The four module issue is a limitation of the memory controller built onto the Athlon 64 itself, it's not just with this board, the same would apply to any Athlon 64 platform. This is supposed to be fixed with the next revision of the A64 CPU's. As to the Geil RAM, the big question mark is, will this RAM even be supported? You would probably be better off sticking with 1 Gig for now or going with a P4 system instead if you absolutlely must have 2 Gigs.

 

[mwarner]

I have recently built an Athlon 64 system with 4GB of memory (4x1GB DIMMs), so I might be able to give you a little advice.

If you want to run 2GB of memory it would be much wiser to go for 2x1GB DIMMs rather than 4 DIMMs. All boards will reduce the memory speed to DDR333 if all four banks are populated and, although this can be changed in the BIOS, you may experience additional problems - especially if you try to use tight timings! Few memory manufacturers even try 4 DIMMs in a system and even fewer say they will actually work in a set of four.

Here are a few links you might find useful:

Asus qualified vendor list for memory modules:
http://www.asus.com/products/mb/socket939/a8nsli-d/qvl.htm

My post on Corsair's forum trying to get some info about running 4GB of memory:
http://www.houseofhelp.com/forums/showthread.php?p=179812#post179812

Mike

 

[imported_BIOSMonkey]

Ugh. Tough decision....

I went ahead and ordered my parts last night, but did not get any memory. My reasoning was that I would spend around the same amount to get the new system to 2gb anyway, the only difference would be whether I would leave the 1gb of fast mem in a system I would no longer use (actually the wife would get it but she doesnt need 1gb). So for now (and until I cleared this up) I decided to just use the 1gb Corsair and bought a cheap 512mb stick for $36 to run in my current setup.

Thanks for the info about the AMD64...I did not know that it was an issue with the mem controller in the proc. My exact DDR part number is CMX512-3200LLPT, which is 2 bank, and based on information in the above links the AMD64 will drop down to DDR333 with more than 6 banks. That sucks.

As for the P4 option, that was not a consideration as this system was designed to last me for awhile (it was expensive!) and I liked the ability to upgrade the proc to dual core without changing the motherboard. I do not intend to use SLI, but like having that second 16x slot for the future (I mainly needed the raid function in the deluxe version).

I know that 16x is primarily for graphics, but you never know. I wonder what interface these new physics processors are going to require...


FYI here is what I got:
Silverstone TJ06 black case, with SS fan controller and SS IO box
Silverstone Zeus 550 PS
Asus A8N-SLI Deluxe
AMD64 3500+
WD Raptor 74gb, 4 Hitachi 160gb (2 for RAID0 and 2 for RAID1)
Samsung DVD/CDROM
NEC 3520 Dual DVD/CD burner
Mitsumi floppy/CF/SD/etc combo drive
MSI Radeon X800XL
Audigy 2 gamer
XP Pro w/ SP2 OEM

 

[Peter]

Once more, this is a limitation of DDR400 operation in itself, not the AMD memory controller. You can only have this many connectors, length of PCB trace and most importantly number of RAM chips on a signal before it degrades enough to break 200 MHz operation.

Thus, setups with fewer DIMMs and/or fewer RAM chips on those DIMMs are always to be preferred.

Besides, the real world performance impact of slower RAM operation isn't as big on AMD64 as pure memory benchmarks would make you think. Not at all, in fact.

 

[Promethply]

If I were you , I would get 2 Geil 1GB sticks, since this will give you more room should you decide to increase you RAM to 4GB in the future.

BTW, the latest A8N-SLI BIOS will detect all 4GB of memory correctly.

 

[ohnnyj]

You can manually set the speed back up to DDR400 on the A8N-SLI Deluxe. I have four sticks of Corsair 3200XL running at these speeds. However, one thing you cannot do is a command rate of 1T. As such I think the 1GB sticks would probably be a good way to go. Either way you aren't going to get much of an overclock, the Geil w/subpar timings and having four sticks usually limits overclockability.

 

[jose]

So, the new Rev "E" cores don't make a difference then.

Right now your able to run 4 mem sticks at ddr400 & 2T, the Venice core doesn't change this.

Regards,
Jose

 

[ohnnyj]

Originally posted by: jose
So, the new Rev "E" cores don't make a difference then.

Right now your able to run 4 mem sticks at ddr400 & 2T, the Venice core doesn't change this.

Regards,
Jose

I was under the impression that the Venice core could do DDR400 & 1T.

 

[jose]

Not according to the reviews..
http://www.xbitlabs.com/articles/cpu/display/athlon64-venice.html

Regards,
Jose

 

[mofrack]

The fact that Venice will allow 4 songle sided DIMMS to do DDR400 at 1T and 4 double sided DIMMS to work AT ALL (at DDR400 2T) is nice.

 

[Peter]

It's not like 4 DS DIMMs didn't work before, albeit at 166 MHz. Heck, there are mainboard designs that have eight (!) DIMM slots per CPU, and these work too.

But yes, the memory controllers in rev. E processors are said (and now apparently confirmed) to push the limits for 200 MHz 1T/2T operation one population count further.

 

[ohnnyj]

Originally posted by: mofrack
The fact that Venice will allow 4 songle sided DIMMS to do DDR400 at 1T and 4 double sided DIMMS to work AT ALL (at DDR400 2T) is nice.

How can you tell single vs double? Is it that there are chips on each side of the PCB = double sided?