S3 Graphics Chrome S27We've not covered S27 before in depth, but it is part of the Chrome S20 family which we covered in a quick preview here. I'll expand on Tarinder's spec sheet a bit, here, comparing it to the NVIDIA and ATI GPUs it competes against, as he did.
|Spec||S3 Chrome S27||NVIDIA NV43||ATI RV515|
|Process and Fab||Fujitsu 90nm||TSMC 110nm||TSMC 90nm|
|DirectX Shader Model||2.0||3.0||3.0|
|Basic GPU Config (VP/FP/ROP)||4/8/8||4/8/4||2/4/4|
|Vertex Shader||VS2.0, 5D FP32, MADD||VS3.0, 5D FP32, MADD, texld, branch||VS3.0, 5D FP32, MADD, branch|
|Fragment Shader||PS2.0, 4D FP24, MADD, texld||PS3.0, 4D FP32, ADD + MADD, texld, branch||PS3.0, 4D FP32, ADD + MADD, texld, branch|
|ROP||4x Int OGSS (1 sample/cycle), 1x Z||4x Int MSAA (2 samples/cycle), 2x Z, FP/FX16 blender||6x FP MSAA (2 samples/cycle), 2x Z, FP/FX16 blender|
|Memory Interface||128-bit, crossbar, GDDR->GDDR3||128-bit, crossbar, GDDR->GDDR3||128-bit external, crossbar, GDDR->GDDR4|
|Texturing||8 samplers, 8 FP24 address, bilinear base filter, up to 16x aniso||8 samplers, 8 FP32 address, bilinear base filter, up to 16x aniso||4 samplers, 4 FP32 address, bilinear base filter, up to 16x aniso|
|Display output||1 x single-link DVI-D TMDS, 1 x analogue VGA||2 x single-link DVI-D TMDS, PureVideo||2 x dual-link DVI-D TMDS, Avivo|
[advert] Definitely last-gen in terms of D3D9 Shader Model support, S27 makes up for it by using Fujitsu's 90nm low-k manufacturing to clock the chip as high as 700MHz. Paired with memory at the same basic frequency (some 1.4GHz DDR), the 4/8/8 configuration S27 should do decently with what's it has, on paper at least.
It's easy to dismiss the lack of multisample antialiasing on a part like S27, especially in modern games where you'll likely want to use all available GPU power just to shade the basic pixel output, but it is lacking in overall IQ because of it. Ordered-grid supersampling is such a killer of performance that, even on older games where it'd be feasible to turn on AA on boards able to multisample depth to remove aliasing, you'll hesitate before turning it on with S27.
Other than that, it's got the on-paper specs to do something useful in the mid-range and low-end spaces, at the right price point, should image quality be up to snuff. We're happy to report that even without a proper image analysis to visibly demonstrate it, the S27 has good basic IQ available to it, largely via decent texture filtering hardware.
Of course there's multi-GPU available via MultiChrome, and we'll investigate that along with single board performance in due course.
Want a peek at the boards?