Review: Geforce 8400GS pitted against 8500GT
Nvidia allowed some selected partners to produce and sell Geforce 8400GS cards despite the fact that they were originally planed for OEM's only. Zotac showed its versions of Geforce 8400GS on Computex, and from June 9 the cards can be found in retail. The suggested prices for Zotac cards are 59USD/€55 or $69USD/€59 for passively cooled card, but we hope that prices will go down a bit very soon.
The more interesting card is the passively cooled version, which allows the transfer of sound over DVI port, and that's the one we have on test today. The card's full name is Zotac GeForce 8400GS 256MB GDDR2 TC V/D/VO, and you can also find it under the code name ZT-84SEG2P-HSL. We will go back to audio and HDMI a bit later, now lets take a look at why Geforce 8400GS is the cheapest DirectX 10 card on the market.
Geforce 8400GS is based on the G86 GPU, the same one that is used on Geforce 8500GT cards. Core clock is the same, 450MHz, although our Zotac 8400GS works at 459MHz. We mentioned that Zotac has two versions of 8400GS cards, the passively cooled which we have on in our lab today, and another one, low profile card cooled by a small fan.
Memory clocks are the same on both Zotac 8400GS cards, 800MHz, the same clock found on reference 8500GT cards. The fan cooled card doesn't feature sound over DVI so you don't get the HDMI adapter in the box.
Now lets take a look at the most important thing that makes Geforce 8400GS so cheap and so behind its older brother Geforce 8500GT. Of course we are talking about the crippled memory interface, 64bit on this card compared to a 128bit bus on a Geforce 8500GT.
The end result is 6.4GB/s of memory bandwidth versus 12.8GB/s on the 8500GT. Luckily, the card has 256MB of memory, and uses Hynix brand chips at 400MHz. Two memory modules are located at the front of the card, or should we say 128 MBs, while the other 128MB are resting on the back of the card.
The following details are identical to the Geforce 8500GT: 16 Stream processors, 8 Texture Filtering units, 8 Texture Addressing units, and 4 ROP's. Shaders are clocked at 900MHz.
The card is DirectX 10 compliant, and Shader Model 4.0 is supported. Other features are : high dynamic-range (HDR) lighting and the second generation Nvidia PureVideo, called PureVideo HD VP2.
Geforce 8400GS is intended for a Vista user who doesn't want integrated graphics but wants decent video performance and HD-DVD and Blu-ray capability in HDTV 1080p quality. For all those lucky guys who have HDMI TV's, Zotac supplied DVI to HDMI adapters. You can fully use that adapter since it is capable of transferring digital video and audio signal over a DVI connector, and over that HDMI cable to your HDMI capable TV.
The credits for all this go to the little SPDIF connector on the card to which you just have to connect a supplied digital audio cable that is bundled with the card. The SPDIF connector can be found in upper part of the card, next to the heatsink. Unfortunately, because of a malfunction on our test monitor, we couldn't check out the quality of sound, for which Zotac guarantees noiseless quality. Beside the Single-Link DVI out, you can also find VGA and HDTV-Out.
The box is average in size, and beside the Zotac 8400GS card you get a CD with drivers, DVI to HDMI adapter (with sound), SPDIF cable (only the passively cooled one) and S-Video/Composite adapter.