Does single sided RAM alwas = high density?

[asand1]

In researching, I have found that double sided RAM is generally associated with low density, while single sided is associated with high density RAM. My ASUS K8N is currently running (1) 512 double sided stick, and (2) 256 single sided sticks, and the PC is showing roughly 1 Gb at 333Hz.
Furthermore, my MB manual does not indicate the density required for this board, however there is a chart showing "memory configurations" for double sided and single sided chips. I have double, single, single, and it is running 333 just as the manual states. The "DDR Qualified Vendors List" shows about a 50/50 mix of SS and DS chips, with 100% of 512MB being DS.
Is it possible that an older DESKTOP MB was intended to run high density RAM? Does density only become an issue over 1Gb/stick?

This is with Linux Mint 17 Xfce

aaron@aaron-K8N ~ $ vmstat -s
   1025820 K total memory
    939812 K used memory
    380656 K active memory
    440244 K inactive memory
    86008 K free memory
    26136 K buffer memory
    386452 K swap cache
   1046524 K total swap
    13920 K used swap
   1032604 K free swap
    281682 non-nice user cpu ticks
    21776 nice user cpu ticks
    79591 system cpu ticks
    988362 idle cpu ticks
    33131 IO-wait cpu ticks
      1 IRQ cpu ticks
     4500 softirq cpu ticks
      0 stolen cpu ticks
   1046079 pages paged in
   1412568 pages paged out
     843 pages swapped in
     3575 pages swapped out
   4103556 interrupts
   15915643 CPU context switches
  1408052833 boot time
     4183 forks

aaron@aaron-K8N ~ $ sudo dmidecode --type 17
[sudo] password for aaron: 
# dmidecode 2.12
SMBIOS 2.3 present.

Handle 0x003C, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x003A
	Error Information Handle: Not Provided
	Total Width: 72 bits
	Data Width: 64 bits
	Size: 512 MB
	Form Factor: DIMM
	Set: None
	Locator: DIMM0
	Bank Locator: BANK0
	Type: DDR
	Type Detail: Synchronous
	Speed: 333 MHz
	Manufacturer: Manufacturer0
	Serial Number: SerNum0
	Asset Tag: AssetTagNum0
	Part Number: PartNum0

Handle 0x003E, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x003A
	Error Information Handle: Not Provided
	Total Width: 72 bits
	Data Width: 64 bits
	Size: 256 MB
	Form Factor: DIMM
	Set: None
	Locator: DIMM1
	Bank Locator: BANK1
	Type: DDR
	Type Detail: Synchronous
	Speed: 333 MHz
	Manufacturer: Manufacturer1
	Serial Number: SerNum1
	Asset Tag: AssetTagNum1
	Part Number: PartNum1

Handle 0x0040, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x003A
	Error Information Handle: Not Provided
	Total Width: 72 bits
	Data Width: 64 bits
	Size: 256 MB
	Form Factor: DIMM
	Set: None
	Locator: DIMM2
	Bank Locator: BANK2
	Type: DDR
	Type Detail: Synchronous
	Speed: 333 MHz
	Manufacturer: Manufacturer2
	Serial Number: SerNum2
	Asset Tag: AssetTagNum2
	Part Number: PartNum2

[asand1]

Re: Does single sided RAM alwas = high density?

Nevermind, I found this;

High density RAM

In the context of the 1 GB non-ECC PC3200 SDRAM module, there is very little visually to differentiate low density from high density RAM. High density DDR RAM modules will, like their low density counterparts, usually be double-sided with eight 512 Mbit chips per side. The difference is that for each chip, instead of being organized in a 64Mx8 configuration, it is organized with 128 Mbits and a data width of 4 bits, or 128Mx4.

High density memory modules are assembled using chips from multiple manufacturers. These chips come in both the familiar 22 x 10 mm (approx.) TSOP2 and smaller squarer 12 x 9 mm (approx.) FBGA package sizes. High density chips can be identified by the numbers on each chip.

High density RAM devices were designed to be used in registered memory modules for servers. JEDEC standards do not apply to high-density DDR RAM in desktop implementations.[citation needed] JEDEC's technical documentation, however, supports 128Mx4 semiconductors as such that contradicts 128x4 being classified as high density. As such, high density is a relative term, which can be used to describe memory which is not supported by a particular motherboard's memory controller.

[chozo4]

Re: Does single sided RAM alwas = high density?

Back in the days older motherboards actually had issues with High-density sticks which at the time would be seen as say.. 4 chips on one side for instance versus the usual 8. Then you had those with issues with double-sided versus single sides so it was a real mess. This was back in the old socket 7/Pentium II days mind you.

As for the 'qualified ram list'... I would pay no mind to it as they never see updates and are only a pre-release list during initial board testing. I've never used ram on any list and yet to experience any issues using them stable. The only thing you would need to mind is different timings on mixing sticks is all so may have to adjust them manually in rare cases. My Samsung 4gb LowProfile DDR3L ram isn't on my current Gigabyte 880gma-usb3 'supported ram' list either and overclocks without problems. My other setup using an ASRock 939DualSata-II uses a mix of 2 different OCZ models and a pair of Low latency Corsair models each 512mb for a total of 2gb. Neither of the 3 types are on a supported list and have no issue either.

As for how much per stick... the basic rule of thumb for maximum per stick is the max supportable by the board divided by the ram slot count. So max 32gb with 4 slots would be 8gb per stick maximum for instance so other than that there is no issue above an (X) amount per stick until that region. Many boards do support higher than 'supported' but then you'd just have to try it otherwise and see.

[brethin]

Re: Does single sided RAM alwas = high density?

Does single sided RAM always = high density?

NO it doesn't.

It depends on the chip configuration and the size of the stick.

The general visual rule is double sided sticks (8 chips on each side) are Low Density but it is not always 100% true, more like 98%.

Many single sided sticks (8 chips on one side) can be low density but again it depends on the chip configuration and the size of the stick.

As for chipsets that will use Low or High Density it depends on the chipset. To be safe all will use low density so if your not sure what your chipset supports go low density.

Most Intel and Apple chipsets require Low Density.

Several other chipsets (ALI, SiS, ViA, etc will use both but it is chipset specific.

[larrymoencurly]

Re: Does single sided RAM alwas = high density?

I don't think it's just the density that matters but the number of address lines used because around 2000, Fry's had a special on 80GB Maxtor hard drives for $50, after rebate, and a 256MB memory module was included. The module had 16 DRAM chips, but it didn't work with my 440BX chipset motherboard because each chip was 32Mx4, rather than the more common 16Mx8.