Intel ATOM CPU's vs. compatible chipsets

Note: this page is out of date. I've added a page for the Atom family into my table of Intel single-socket CPU's.

	N270	Z500 series	N400 series (N4502)		D410	D510	D410	D510	230	330	Z6004 series SoC	E6005 series SoC	D2500	D2700	N2600	N2800
Chipset	i945GSE GMCH+ICH7	US15W SCH	NM10 ICH	ICH8M (Advantech)	NM10 ICH		ICH9R ICH (Supermicro)		i945GC GMCH+ICH7		MP20 PCH	EG20T PCH	NM10 ICH (or ICH8/ICH9)
CPU-chipset link	FSB	FSB	DMI		DMI				FSB		PCI-e	PCI-e	DMI
VGA on-chip where	GMCH GMA950	SCH GMA500!3	CPU GMA3150		CPU GMA3150				GMCH GMA950		CPU GMA600!3	CPU GMA600!3	CPU GMA5650		CPU GMA3600
CPU nm	45	45	45		45				45		45	45	32
# cores	1	1	1		1	2	1	2	1	2	1	1	2
L1 I+D cache	32+24 kB	32+24 kB	32+24 kB		32+24 kB per core				32+24 kB per core		?	32+24 kB	?
L2 cache	512 kB	512 kB	512 kB		512 kB per core				512 kB per core		?	512 kB	512 kB per core
other CPU features	HT XD SSE2 SSE3 SSSE3	HT VT1 XD1 SSE2 SSE3 SSSE3	x86-64 HT XD SSE2 SSE3 SSSE3		x86-64 HT XD SSE2 SSE3 SSSE3				x86-64 HT XD SSE2 SSE3	x86-64 HT XD SSE2 SSE3 SSSE3		HT VT SSE2 SSE3 SSSE3	x86-64 XD	x86-64 HT XD	x86-64 HT XD	x86-64 HT XD
SATA	4 (ICH7M=2) (ICH7U=0)	N/A	2	3	2		6		4 (ICH7M=2) (ICH7U=0)			2	2
IDE	1	1	N/A	1	N/A		N/A		1			N/A	N/A
USB	8	8	8	10	8		12		8		likely	6H+1C	8
PCI-e x1	4 (ICH7R=6) (ICH7U=0)	2	4		4		6		4 (ICH7R=6) (ICH7U=0)			3?	4
PCI 32b REQ+GNT	6 (ICH7U=3)	N/A	2	3	2		4		6 (ICH7U=3)			N/A	2
Ethernet on-chip	100 Mb (ICH7U=N/A)	N/A	100 Mb (?)	1 Gb	100 Mb (?)		1 Gb		100 Mb (ICH7U=N/A)			1 Gb	100 Mb (?)

1. not all models
2. The N450 looks like a mobile-focused stripped-down sibling (SODIMM support, lower-clocked VGA subsystem, half the TDP) of the D410 (which looks more like a "desktop" - nettop? part).
3. The GMA500, integrated in the SCH, as well as the GMA600, integrated in the 600 series ATOM CPU's, are not the traditional Intel IGP's. It is an IP core purchased by Intel from PowerVR (GMA500=SGX535). It seems to have some interesting features in terms of HW acceleration, but lacks an open-source driver for Xwindows (Linux/BSD), likely due to disclosure/licensing issues.
4. "Ultra mobile" family. The press release in may 2010 heralded "the first ATOM for smartphones and tablets". By February 2011, there's still only the datasheet. The Z600 family isn't mentioned on the Intel web site, and Google can't find any particular products based on those chips... Seems like the Z600 hasn't quite taken off.
5. "Embedded" family. The CPU has on-chip Intel HD Audio, LPC, SPI, legacy PC i8254 + i8259 => it's really an x86 System-on-a-Chip (SoC). The EG20T has on-chip CAN and 4x UART.
   There is a somewhat special sub-family: the E6x5 series, containing an Altera FPGA in the package (hence the somewhat higher TDP figures). Seems to be an OEM-only version, don't expect this one on general-purpose PC-compatible boards.

• Hardware support for 64bit ("long long") integer math, twice the number of general purpose registers, twice the number of SSE registers = more CPU horsepower for intensive number crunching. See the relevant Wikipedia entry.
• Support for more memory? (full 4GB and more) Not much of an advantage. Not until Intel provides ATOM-compatible memory controllers with support for 8 GB or more.
  The models featuring an integrated memory controller hardly make use of it: the N450 supports 2 GB maximum, the D410/510 support 4 GB maximum (64bit addressing saves something over 0.5 GB here).
  The 230/330 CPU's seem to have 36bit addressing in the FSB. But: the officially supported i945 GMCH supports 2 or 4 GB maximum, depending on desktop/mobile flavour, and only 32bit FSB addressing anyway (no point in 64bit addressing). Based on FSB clock (533 MHz), the 230/330 could theoretically be combined with the 965 family desktop GMCH or i3000/3010 entry-level server MCH to achieve 8GB RAM. Would you want an ATOM combined with a high-performance 65nm chipset? What's the point of using an ATOM, right?
  The "3 series" and "4 series" chipsets can do 4 to 16 GB of RAM, but start at 667 MHz FSB (combined with lower RAM capability at that FSB clock).

Feedback / updates are welcome :-)
Frank Rysanek of FCC prumyslove systemy s.r.o. [ rysanek AT fccps DOT cz]