BlueSmoke - HDD Article : IBM Deskstar 40GV

		Date	: Aug 31st, 2001
		Category	: Storage
		Manufacturer	: IBM
		Author	: Jin-Wei Tioh

The IBM Deskstar 40GV is Big Blue's latest low-cost, entry-level 5400 RPM IDE hard disk solution. It packs 20GB/platter to achieve a 2-platter flagship capacity of 40GB. This move by IBM is rather odd, as they usually utilize a 1" low-profile, 5-platter design. Had this design been utilized, the 40GV would have had a flagship capacity of 100GB! (achieving a world's first in the process). The drive packaging is your standard issues ESD bag, offering little protection against external shocks. Specified seek times are a conservative 9.5ms, and the buffer size is a tad underwhelming 512KB (versus the Seagate U5's 1MB). Additionally, the 40GV ships exclusively with the ATA-100 interface, though older it will generally work just as well on older interfaces (ATA-66 and ATA-33). In spite of it's value-class status, an unusual full 3-year warranty backs the unit.

Previously, we have grilled the Seagate U5, U10 and Quantum lct20 on our storage testbed. Let's take a look at how the 40GV stacks up.

Testbed Low-Level Measurements Methodology

WinBench 99 clocks the 40GV at 15ms, definitely much better than that of both the U5 and lct20. Subtracting 5.6ms (the rotational latency of all 5400rpm drives) yields a measured seek time of 9.4milliseconds. Big Blue's specs are right on the money, something not too common these days. Being a 20GB/platter unit, we expected the Deskstar 40GV's STRs (sequential transfer rates) to be nothing short of stellar. The outer-zone STR is 31.2MB/s, virtually a tie with the Seagate U5. The inner-zone STR is quite another matter however, with the 40GV curiously lagging behind, coming out just slightly ahead of the Seagate U10.

Clearly, the fight here is between the Deskstar 40GV and the U5. Let's see how to these scores translate into higher-level performance.

Testbed Disk WinMarks Methodology

HDD	Business	High-End
IBM Deskstar 40GV (40GB ATA-100)	4050	11500
Quantum Fireball lct20 (10GB ATA-100)	2790	7890
Seagate U Series 5 (40.8GB ATA-100)	3800	11400

In a reversal of fortune, it is the Deskstar 40GV that comes out tops. However, as in the STR scores, it is still a close race between the 40GV and U5, with the 40GV leading by an average of 4%.

Decent Disk WinMarks are only part of the whole picture. Let's see what light Intel's IOMeter casts on the issue.

Testbed IOMeter - Total I/Os Per Second Methodology

HDD	Load	Access Pattern
		File Server	Workstation	Database	Video Workstation
IBM Deskstar 40GV (40.0GB ATA-100)	Linear	71.66	85.15	71.79	3136.53
	Light	106.22	118.65	104.63	3504.76
	Moderate	128.00	141.30	126.62	3504.72
	Heavy	143.43	156.94	142.72	3500.80
Quantum Fireball lct20 (10.0GB ATA-100)	Linear	50.77	60.35	50.73	2189.65
	Light	73.79	83.18	72.57	2189.88
	Moderate	84.51	95.70	84.27	2190.18
	Heavy	89.85	101.50	90.22	2190.13
Seagate U Series 5 (40.0GB ATA-100)	Linear	51.31	59.15	50.14	2823.54
	Light	66.44	73.16	58.91	2854.19
	Moderate	81.10	87.08	64.71	2854.29
	Heavy	93.89	96.78	77.95	2854.12

The Deskstar 40GV really starts to shine in IOMeter. A quick glance at the table shows the 40GV as having the highest number of I/Os per second under all loads and access patterns.

Interestingly, the 5400 RPM Seagate U5 does not seem to fare as well compared to the 4500 RPM Fireball lct20, generally scoring lower except under the Video Workstation access pattern. The purpose of the Video Workstation access pattern (which consists of 100% sequential writes) is to simulate a digital NLE environment, where video is captured to the hard drive. Thus, the faster a hard drive can write, the more suitable it is for storing bandwidth intensive data like digitized video. This seems to be more of Seagate's forte.

The Deskstar 40GV runs cool to the touch even after extended periods of usage. As with the Deskstar 60GXP, the drive's idle noise is indiscernible above our testbed's power supply, and seeks were comparatively muted and shallow. In these respects, the 40GV rivals the lct20 - a 4500 RPM unit. Under most conditions, the 40GV, U5 and lct20 will run fine without any form of active cooling.

All in all, the 40GV is a rather attractive package. Despite its slightly disillusioning 512KB buffer, this value drive offers category-leading performance. It scores well under WinBench 99 and excels under IOMeter, is fast, cheap, quiet and cool. If you are in need of a 5400 RPM HDD, definitely get the 40GV if it is available.

IBM Deskstar 40GV (DTLA-305040)
Other Models :	DTLA-305030 (30 GB), DTLA-305020 (20 GB)